CN113984543A - Non-thermal steady state mechanical testing device based on mechanical difference method and application method thereof - Google Patents
Non-thermal steady state mechanical testing device based on mechanical difference method and application method thereof Download PDFInfo
- Publication number
- CN113984543A CN113984543A CN202111586239.8A CN202111586239A CN113984543A CN 113984543 A CN113984543 A CN 113984543A CN 202111586239 A CN202111586239 A CN 202111586239A CN 113984543 A CN113984543 A CN 113984543A
- Authority
- CN
- China
- Prior art keywords
- pressure head
- temperature
- displacement
- data
- mechanical
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/08—Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces
- G01N3/18—Performing tests at high or low temperatures
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/02—Details
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/0001—Type of application of the stress
- G01N2203/0003—Steady
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/0014—Type of force applied
- G01N2203/0016—Tensile or compressive
- G01N2203/0019—Compressive
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/0058—Kind of property studied
- G01N2203/0069—Fatigue, creep, strain-stress relations or elastic constants
- G01N2203/0075—Strain-stress relations or elastic constants
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/0202—Control of the test
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/022—Environment of the test
- G01N2203/0222—Temperature
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/022—Environment of the test
- G01N2203/0222—Temperature
- G01N2203/0228—Low temperature; Cooling means
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/025—Geometry of the test
- G01N2203/0258—Non axial, i.e. the forces not being applied along an axis of symmetry of the specimen
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/06—Indicating or recording means; Sensing means
- G01N2203/067—Parameter measured for estimating the property
- G01N2203/0676—Force, weight, load, energy, speed or acceleration
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/06—Indicating or recording means; Sensing means
- G01N2203/067—Parameter measured for estimating the property
- G01N2203/0682—Spatial dimension, e.g. length, area, angle
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/06—Indicating or recording means; Sensing means
- G01N2203/067—Parameter measured for estimating the property
- G01N2203/0694—Temperature
Landscapes
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
The invention discloses a non-thermal steady state mechanical testing device based on a mechanical difference method and an application method thereof, wherein the device comprises a temperature control box, a force sensor, a lower pressure head mechanism, an upper pressure head mechanism, a cross beam and a displacement testing mechanism; the force sensor, the lower pressure head mechanism, the upper pressure head mechanism and the displacement testing mechanism are coaxially and sequentially arranged along the vertical direction, and the force sensor is abutted against the bottom of the lower pressure head mechanism; the displacement testing mechanism sequentially penetrates through the cross beam and the upper pressure head mechanism along the vertical direction and then extends to be abutted against the lower pressure head mechanism. According to the invention, the displacement testing mechanism is introduced into the upper pressure head mechanism and the cross beam, the displacement testing mechanism is matched with the cross beam to accurately regulate and control the distance between the upper pressure head and the lower pressure head, the temperature control box is used for regulating and controlling the temperature change, so that any one of temperature data, stress data and displacement data is kept constant, the relation between the other two data is obtained, and the accurate test of the response behavior of the material under three conditions of constant displacement, constant force and constant temperature is realized.
Description
Technical Field
The invention relates to the field of material testing, in particular to a non-thermal steady-state mechanical testing device based on a mechanical difference method and an application method thereof.
Background
Under the condition of a specific displacement boundary, the driving load of a test piece under the action of heat, electricity, magnetism, light and the like is a problem to be solved urgently in the field of structural design in the current material evaluation. When the shape memory alloy and the like are used for some special unfolding mechanisms, the driving force which can be generated by the material during the temperature rise and the phase change needs to be tested; when a building structure is designed in a cold area, the expansion force of frozen soil and the like during freezing expansion needs to be represented; when the glue is used for packaging electronic devices, the shrinkage force generated by the glue or the acting force which can be generated by pasting the device on the glue under the heating condition when the glue is solidified needs to be tested. However, the existing testing machines and related techniques have great difficulty in solving this problem because: the displacement response output by the traditional testing machine is not the real displacement of two ends of the test piece, the testing machine usually tests the displacement of the cross beam, and the accuracy of the testing machine is influenced by the rigidity of the cross beam, the rigidity of a frame of the testing machine and the rigidity of an upper connecting structure and a lower connecting structure of the test piece; in addition, under the condition of variable temperature, the accurate control of the displacement of the two ends of the test piece can be influenced by the expansion with heat and the contraction with cold of the structure. The existing displacement testing technology, such as a strain gauge, can not realize the displacement control of the test piece under the condition of variable temperature; the extensometer can be used for displacement control of a test piece with a large size, but cannot be used for a test piece with a small size, and has the problem of temperature stability; optical measurement means such as digital image correlation technology can only be used for post-processing of material deformation test, and cannot be combined with a testing machine to realize real-time feedback control. For the problem, no good technical means for solving the problem exists at present. Therefore, the test system for driving the load of the test piece under the action of heat, electricity, magnetism, light and the like under the condition of developing the displacement boundary condition under the accurate and controllable condition has important significance in the fields of scientific research, industry, national infrastructure and the like.
Disclosure of Invention
The invention aims to provide a non-thermal steady-state mechanical testing device based on a mechanical difference method and an application method thereof, which are used for solving the problem that the prior art is difficult to realize accurate measurement and control of the displacement of the end part of a test piece under the condition of variable temperature so as to influence the mechanical testing effect.
In order to solve the above technical problem, a first solution provided by the present invention is: a non-thermal steady state mechanical testing device based on a mechanical difference method comprises a temperature control box, a force sensor, a lower pressure head mechanism, an upper pressure head mechanism, a cross beam and a displacement testing mechanism; the force sensor, the lower pressure head mechanism, the upper pressure head mechanism and the displacement testing mechanism are coaxially and sequentially arranged along the vertical direction, and the force sensor is abutted against the bottom of the lower pressure head mechanism and used for acquiring stress data; a gap for accommodating a sample to be measured is arranged between the lower pressure head mechanism and the upper pressure head mechanism, and the temperature control box is arranged at the position of the sample to be measured in a surrounding manner and is used for controlling the temperature and acquiring temperature data; the displacement testing mechanism sequentially penetrates through the cross beam and the upper pressure head mechanism along the vertical direction and then extends to abut against the lower pressure head mechanism for obtaining displacement data of a sample to be tested; the top of the upper pressure head mechanism is vertically connected with the bottom of the cross beam, the displacement testing mechanism is connected with the top of the cross beam, and the cross beam is used for controlling the change of displacement data or stress data.
Preferably, the non-thermal steady-state mechanical testing device based on the mechanical difference method further comprises a frame, the temperature control box, the force sensor, the lower pressure head mechanism, the upper pressure head mechanism, the beam and the displacement testing mechanism are all arranged in an inner cavity of the frame, the bottom of the force sensor is abutted to the bottom of the inner cavity of the frame, and the beam is in sliding connection with the side wall of the inner cavity of the frame.
Preferably, the lower pressure head mechanism comprises a lower base, a lower pipe body, a lower pressure head seat and a lower pressure head which are coaxially arranged along the vertical direction; the bottom of the lower base is connected with the force sensor, the lower pipe body is fixedly arranged in an inner cavity at the top of the lower base, the top of the lower pipe body is embedded and connected with the bottom of the lower pressure head seat, and the lower pressure head is embedded and arranged at the top of the lower pressure head seat; the lower base is provided with a first water cooling channel, and the inner cavity of the lower pipe body is communicated with an external water cooling device through the first water cooling channel.
Preferably, the upper pressure head mechanism comprises an upper base, an upper pipe body, an upper pressure head seat and an upper pressure head which are coaxially arranged along the vertical direction; the top of the upper base is connected with the bottom of the cross beam, the upper pipe body is fixedly arranged in an inner cavity at the bottom of the upper base, the bottom of the upper pipe body is connected with the top of the upper pressure head base in an embedded mode, the upper pressure head is embedded at the bottom of the upper pressure head base, a gap for accommodating a sample to be detected is reserved between the upper pressure head and the lower pressure head, and the distance between the upper surface of the lower pressure head and the lower surface of the upper pressure head is the displacement data of the sample to be detected; the upper base is provided with a second water-cooling channel, and the inner cavity of the upper pipe body is communicated with an external water-cooling device through the second water-cooling channel.
Preferably, the displacement testing mechanism comprises a sensor fixing piece, a displacement sensor, a first differential rod, a second differential rod and a variable temperature compensation rod; the bottom of the sensor fixing piece is connected with the top of the cross beam, the displacement sensor is embedded in an inner cavity of the sensor fixing piece, and the first differential rod and the second differential rod are arranged in the vertical direction; one end of the first differential rod is connected with the sensor fixing piece, and the other end of the first differential rod penetrates through the cross beam, the upper base and the upper pipe body in sequence and then is connected with the upper pressure head; one end of the second differential rod is connected with the displacement sensor, the other end of the second differential rod penetrates through the cross beam, the upper base and the upper pipe body in sequence and then is coaxially connected with the variable temperature compensation rod, and one end, far away from the second differential rod, of the variable temperature compensation rod is abutted to the lower pressure head.
Preferably, the first differential rod and the second differential rod are made of rigid materials with the same thermal expansion coefficient; when the temperature changes, the upper pressure head and the variable temperature compensation rod meet the following requirements:
L1/ L2=α2/α1
wherein L is1Is the initial length of the upper ram, alpha1Is the thermal expansion coefficient of the upper ram, L2For the initial length of the temperature-changing compensation rod, alpha2The thermal expansion coefficient of the temperature-changing compensation rod.
In order to solve the above technical problem, a second solution provided by the present invention is: an application method of a non-thermal steady-state mechanical testing device based on a mechanical difference method is based on the non-thermal steady-state mechanical testing device based on the mechanical difference method in the first solution, and comprises the following steps: and synchronously acquiring temperature data, stress data and displacement data, controlling the temperature of the temperature control box or the position of the cross beam to keep any one of the data constant, and acquiring the relation between the other two data.
The testing step when the temperature data is constant comprises the following steps: controlling the temperature of the temperature control box, applying the same constant temperature conditions to the lower pressure head, the upper pressure head and the sample to be measured, acquiring stress data by the force sensor, and acquiring displacement data by the displacement sensor; and drawing a displacement-mechanical curve by combining the stress data and the displacement data, wherein the displacement-mechanical curve is the relation between the stress and the displacement of the sample to be detected when the temperature data is constant.
The testing step when the displacement data is constant comprises the following steps: controlling the temperature of the temperature control box, applying the same temperature change condition to the lower pressure head, the upper pressure head and the sample to be measured, acquiring stress data by the force sensor, acquiring displacement data by the displacement sensor, and controlling the position of the cross beam to keep the displacement data constant in the temperature change process; and drawing a temperature-mechanical curve by combining the temperature data and the stress data, wherein the temperature-mechanical curve is the relation between the temperature of the sample to be measured and the stress when the displacement data is constant.
Wherein, the test step when the stress data is constant comprises: controlling the temperature of a temperature control box, applying the same temperature change condition to a lower pressure head, an upper pressure head and a sample to be measured, acquiring stress data by a force sensor, controlling the position of a cross beam to keep the stress data constant in the temperature change process, and acquiring displacement data by a displacement sensor; and drawing a temperature-displacement curve by combining the temperature data and the displacement data, wherein the temperature-displacement curve is the relation between the temperature and the displacement of the sample to be measured when the stress data is constant.
The invention has the beneficial effects that: the invention provides a non-thermal steady-state mechanical testing device based on a mechanical difference method and an application method thereof, wherein a displacement testing mechanism is introduced into an upper pressure head mechanism and a cross beam, the displacement testing mechanism is matched with the cross beam to accurately regulate and control the distance between the upper pressure head and a lower pressure head, a temperature control box is used for regulating and controlling the temperature change, so that any one of temperature data, stress data and displacement data is kept constant, the relation between the other two data is obtained, and the accurate test of the response behavior of a material under three conditions of constant displacement, constant force and constant temperature is realized.
Drawings
FIG. 1 is a schematic structural diagram of an embodiment of a non-thermal steady-state mechanical testing device based on a mechanical difference method according to the present invention;
FIG. 2 is a schematic structural diagram of a component at a central axis position in an embodiment of a non-thermal steady-state mechanical testing device based on a mechanical difference method according to the present invention;
FIG. 3 is a schematic cross-sectional view taken along line B-B of FIG. 2;
in the figure: 1-a temperature control box, 2-a frame body, 3-a force sensor, 4-a lower pressure head mechanism, 41-a lower base, 42-a lower tube body, 43-a lower pressure head seat, 44-a lower pressure head, 5-an upper pressure head mechanism, 51-an upper base, 52-an upper tube body, 53-an upper pressure head seat, 54-an upper pressure head, 6-a cross beam, 7-a displacement testing mechanism, 71-a sensor fixing part, 72-a displacement sensor, 73-a first differential rod, 74-a second differential rod, 75-a temperature-variable compensation rod and 8-a sample to be tested.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.
Referring to fig. 1 to 3, for the first solution of the present invention, the non-thermal steady-state mechanical testing apparatus based on the mechanical difference method includes a frame 2, a temperature control box 1, a force sensor 3, a lower pressure head mechanism 4, an upper pressure head mechanism 5, a beam 6, and a displacement testing mechanism 7; in the inner cavity of the frame body 2, a force sensor 3, a lower pressure head mechanism 4, an upper pressure head mechanism 5 and a displacement testing mechanism 7 are coaxially and sequentially arranged along the vertical direction, a gap for accommodating a sample 8 to be tested is arranged between the lower pressure head mechanism 4 and the upper pressure head mechanism 5, a temperature control box 1 is annularly arranged at the position of the sample 8 to be tested, the top of the upper pressure head mechanism 5 is vertically connected with a cross beam 6, the cross beam 6 is horizontally arranged and is in sliding connection with the side wall of the inner cavity of the frame body 2, and the displacement testing mechanism 7 is connected with the top of the cross beam 6; the bottom of the force sensor 3 is abutted with the bottom of the inner cavity of the frame body 2, and the force sensor 3 is abutted with the bottom of the lower pressure head mechanism 4 and used for acquiring stress data; the displacement testing mechanism 7 sequentially penetrates through the cross beam 6 and the upper pressure head mechanism 5 along the vertical direction and then extends to abut against the lower pressure head mechanism 4, and is used for obtaining the displacement number of the sample 8 to be tested. The following describes the structure of each component in the non-thermal steady-state mechanical testing device based on the mechanical difference method in detail.
Specifically, the lower press head mechanism 4 includes a lower base 41, a lower pipe 42, a lower press head base 43, and a lower press head 44, which are coaxially arranged in the vertical direction; the bottom of the lower base 41 is connected with the force sensor 3, the lower tube body 42 is fixedly arranged in the top inner cavity of the lower base 41, the top of the lower tube body 42 is embedded and connected with the bottom of the lower pressure head seat 43, and the lower pressure head 44 is embedded and arranged on the top of the lower pressure head seat 43; lower base 41 is equipped with first water-cooling channel, and the inner chamber of body 42 communicates with outside water cooling plant through first water-cooling channel down utilizes the water-cooling structure to keep apart force transducer 3 and the top high temperature region of lower pressure head mechanism 4, causes the influence to force transducer 3's measurement when avoiding the control temperature change.
Specifically, the upper ram mechanism 5 includes an upper base 51, an upper pipe body 52, an upper ram seat 53 and an upper ram 54 coaxially arranged in the vertical direction; the top of the upper base 51 is connected with the bottom of the cross beam 6, the upper tube body 52 is fixedly arranged in the bottom inner cavity of the upper base 51, the bottom of the upper tube body 52 is connected with the top of the upper pressure head seat 53 in an embedded mode, the upper pressure head 54 is embedded in the bottom of the upper pressure head seat 53, a gap for accommodating the sample 8 to be measured is reserved between the upper pressure head 54 and the lower pressure head 44, the sample 8 to be measured is clamped through the upper pressure head 54 and the lower pressure head 44, and the distance between the upper surface of the lower pressure head 44 and the lower surface of the upper pressure head 54 is displacement data of the sample to be measured; go up base 51 and be equipped with second water-cooling channel, go up the inner chamber of pipe body 52 and pass through second water-cooling channel and outside water cooling plant intercommunication, utilize the water-cooling structure to keep apart displacement sensor 72 and the bottom high temperature region of last pressure head mechanism 5, cause the influence to displacement sensor 72's measurement when avoiding the control temperature change.
Specifically, the displacement testing mechanism 7 includes a sensor fixing member 71, a displacement sensor 72, a first differential rod 73, a second differential rod 74, and a temperature-varying compensation rod 75; the bottom of the sensor fixing piece 71 is connected with the top of the cross beam 6, the displacement sensor 72 is embedded in an inner cavity of the sensor fixing piece 71, and the first differential rod 73 and the second differential rod 74 are arranged in the vertical direction; one end of the first differential rod 73 is connected with the sensor fixing piece 71, and the other end of the first differential rod penetrates through the cross beam 6, the upper base 51 and the upper pipe body 52 in sequence and then is connected with the upper pressure head 54; one end of the second differential rod 74 is connected to the displacement sensor 72, and the other end of the second differential rod passes through the beam 6, the upper base 51, and the upper tube 52 in sequence and then is coaxially connected to the temperature-changing compensation rod 75, and one end of the temperature-changing compensation rod 75, which is far away from the second differential rod 74, is abutted to the lower pressure head 44.
In the present embodiment, the lower pressure head 44 and the upper pressure head 54 are preferably made of materials with small thermal expansion coefficient and high rigidity, and preferably the rigidity is far greater than that of the material to be measured, so as to reduce the deformation amount in the temperature change process; the first differential rod 73 and the second differential rod 74 should be made of rigid materials having the same thermal expansion coefficient, and preferably, the size and material of the two should be kept the same so as to have the same amount of deformation when affected by temperature. Taking the temperature rise as an example, the lower ram 44 and the upper ram 54 will generate synchronous thermal expansion, and the upper ram 54 is mainly moved, and in order to ensure that the displacement data is always constant, the deformation amount of the upper ram 54 is required to be equal to that of the temperature change compensation rod 75, that is, the following formula is satisfied:
S1=L1×α1×∆t （1）
S2=L2×α2×∆t （2）
S1=S2（3）
the simultaneous expression (1) to (3) gives:
L1/ L2=α2/α1（4）
in the above formulas (1) to (4), S1Is the amount of deformation of the upper ram, S2For varying the amount of deformation of the compensating rod, L1Is the initial length of the upper ram, alpha1Is the thermal expansion coefficient of the upper ram, L2For the initial length of the temperature-changing compensation rod, alpha2The thermal expansion coefficient of the temperature-changing compensation rod.
In this embodiment, the temperature of the temperature control box and the position of the cross beam are controlled by a computer, and the temperature data, the displacement data and the mechanical data are collected and plotted by the computer, so that the control and data integration of the device are simpler and more convenient.
For the second solution of the present invention, the provided application method is based on the non-thermal steady-state mechanical testing apparatus based on the mechanical difference method in the first solution, and includes the following steps: and synchronously acquiring temperature data, stress data and displacement data, controlling the temperature of the temperature control box or the position of the cross beam to keep any one of the data constant, and acquiring the relation between the other two data. Namely, the device can be used for accurately testing three conditions of constant displacement, constant force and constant temperature of a sample to be tested under a non-thermal steady state, and the three testing modes are specifically explained below.
In the first test mode, the test steps when the temperature data is constant are as follows:
1) the movement of the beam 6 is controlled by the computer, so that the sample 8 to be measured is clamped between the lower pressure head 44 and the upper pressure head 54, and the initial contact force at the moment is measured by the force sensor 3, wherein the initial contact force is preferably not a proper value of 0, so as to ensure that the sample 8 to be measured is in a stressed clamping state.
2) The computer controls the temperature control box 1 to keep constant temperature, at the moment, the lower pressure head mechanism 4, the upper pressure head mechanism 5, the variable temperature compensation rod 75 and the sample 8 to be tested keep constant temperature, the computer synchronously records the temperature signal of the temperature control box 1, the constant temperature test time is preset, the position of the cross beam 6 is kept fixed, the force sensor 3 acquires stress data, the displacement sensor 72 acquires displacement data, and the computer draws a temperature-mechanical curve, so that the displacement-mechanical relation of the sample 8 to be tested under the non-thermal steady state condition is obtained.
In the second test mode, the test steps when the displacement data is constant are as follows:
1) the movement of the beam 6 is controlled by the computer, so that the sample 8 to be measured is clamped between the lower pressure head 44 and the upper pressure head 54, and the initial contact force at the moment is measured by the force sensor 3, wherein the initial contact force is preferably not a proper value of 0, so as to ensure that the sample 8 to be measured is in a stressed clamping state.
2) The temperature control box 1 is controlled by the computer to start temperature rise, at the moment, the lower pressure head mechanism 4, the upper pressure head mechanism 5 and the variable temperature compensation rod 75 start to synchronously rise temperature along with the sample 8 to be measured, the computer synchronously records the temperature signal of the temperature control box 1, the computer controls the beam 6 to move in the temperature rise process, so that the distance between the upper surface of the lower pressure head 44 and the lower surface of the upper pressure head 54 is kept constant, namely the displacement data of the sample 8 to be measured is kept constant, the stress signal of the force sensor 3 is synchronously recorded, and the computer draws a temperature-mechanical curve, so that the temperature-mechanical relation of the sample 8 to be measured under the non-thermal steady state condition is obtained.
In the test process, due to heat conduction and expansion and contraction, the lower pipe body 42, the lower pressure head seat 43, the lower pressure head 44, the upper pipe body 52, the upper pressure head seat 53 and the upper pressure head 54 can generate certain thermal expansion elongation along with the rise of temperature, and meanwhile, the sample 8 to be tested is also heated to elongate; on one hand, the frame body 2, the force sensor 3 and the cross beam 6 are not deformed at room temperature, so that the actual distance between the cross beam 6 and the force sensor 3 is not changed; on the other hand, the rigidity of the lower pressure head mechanism 4 and the upper pressure head mechanism 5 is much higher than that of the sample 8 to be measured, so that the sample 8 to be measured is compressed and shortened by the lower pressure head 44 and the upper pressure head 54, and the displacement state of the two ends of the sample 8 to be measured needs to be adjusted in real time as the sample 8 to be measured is required to adapt to temperature change conditions and perform a test. At this time, the displacement sensor 72 measures the distance between the upper surface of the lower pressure head 44 and the lower surface of the upper pressure head 54 and feeds back the distance to the computer, and because of thermal expansion, the computer needs to control the beam 6 to move upwards so as to drive the upper pressure head 54 to move upwards, so that the distance between the upper surface of the lower pressure head 44 and the lower surface of the upper pressure head 54 is kept constant, and further, the length of the sample 8 to be measured is kept unchanged in the test process, the thermal expansion force of the sample 8 to be measured is measured by the force sensor 3 and then fed back to the computer for recording, and in combination with synchronously recorded temperature information, an accurate result of the temperature-stress relation can be obtained under the condition of constant displacement.
In the third test mode, the test steps when the stress data is constant are as follows:
1) the movement of the beam 6 is controlled by the computer so that the sample 8 to be measured is clamped between the lower pressing head 44 and the upper pressing head 54, and the initial contact force at this time is measured by the force sensor 3 and is not 0.
2) The temperature control box 1 is controlled by the computer to start temperature rise, at the moment, the lower pressure head mechanism 4, the upper pressure head mechanism 5 and the variable temperature compensation rod 75 start to synchronously rise temperature along with the sample 8 to be measured, the computer synchronously records the temperature signal of the temperature control box 1, the computer controls the beam 6 to move in the temperature rise process, the mechanical data measured by the force sensor 3 keeps a constant value of the initial contact force, the displacement data of the displacement sensor 72 is synchronously recorded, and the computer draws a temperature-displacement curve, so that the temperature-displacement relation of the sample 8 to be measured under the non-thermal steady state condition is obtained.
In the test process, due to heat conduction and expansion and contraction, the lower pipe body 42, the lower pressure head seat 43, the lower pressure head 44, the upper pipe body 52, the upper pressure head seat 53 and the upper pressure head 54 can generate certain thermal expansion elongation along with the rise of temperature, and meanwhile, the test sample 8 also can generate thermal elongation; on one hand, the frame body 2, the force sensor 3 and the cross beam 6 are not deformed at room temperature, so that the cross beam 6 and the force sensor 3 do not contribute to stress change; on the other hand, the rigidity of the lower pressure head mechanism 4 and the upper pressure head mechanism 5 is much higher than that of the sample 8 to be measured, so that the sample 8 to be measured is compressed and shortened by the lower pressure head 44 and the upper pressure head 54, and contribution is made to stress change, so that the displacement states of the two ends of the sample 8 to be measured need to be adjusted in real time. At this moment, the force sensor 3 measures mechanical data and feeds the mechanical data back to the computer, due to thermal expansion, the computer needs to control the beam 6 to move upwards so as to drive the upper pressure head 54 to move upwards, so that the pressure is weakened, further the tested sample 8 is ensured to keep unchanged in the testing process, the displacement sensor 72 measures the displacement data of the tested sample 8 and feeds the displacement data back to the computer for recording, and the accurate result of the temperature-displacement relation can be obtained under the condition of constant stress by combining with synchronously recorded temperature information.
The invention provides a non-thermal steady-state mechanical testing device based on a mechanical difference method and an application method thereof, wherein a displacement testing mechanism is introduced into an upper pressure head mechanism and a cross beam, the displacement testing mechanism is matched with the cross beam to accurately regulate and control the distance between the upper pressure head and a lower pressure head, a temperature control box is used for regulating and controlling the temperature change, so that any one of temperature data, stress data and displacement data is kept constant, the relation between the other two data is obtained, and the accurate test of the response behavior of a material under three conditions of constant displacement, constant force and constant temperature is realized.
The above-mentioned embodiments only express the embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (10)
1. A non-thermal steady state mechanical testing device based on a mechanical difference method is characterized by comprising a temperature control box, a force sensor, a lower pressure head mechanism, an upper pressure head mechanism, a cross beam and a displacement testing mechanism;
the force sensor, the lower pressure head mechanism, the upper pressure head mechanism and the displacement testing mechanism are coaxially and sequentially arranged along the vertical direction, and the force sensor is abutted against the bottom of the lower pressure head mechanism and used for acquiring stress data;
a gap for accommodating a sample to be measured is arranged between the lower pressure head mechanism and the upper pressure head mechanism, and the temperature control box is arranged at the position of the sample to be measured in a surrounding manner and is used for controlling the temperature and acquiring temperature data;
the displacement testing mechanism sequentially penetrates through the cross beam and the upper pressure head mechanism along the vertical direction and then extends to be abutted against the lower pressure head mechanism, so that displacement data of a sample to be tested can be obtained;
the top of the upper pressure head mechanism is vertically connected with the bottom of the cross beam, the displacement testing mechanism is connected with the top of the cross beam, and the cross beam is used for controlling the change of the displacement data or the stress data.
2. The mechanical differential method-based non-thermal steady-state mechanical testing device of claim 1, wherein the mechanical differential method-based non-thermal steady-state mechanical testing device further comprises a frame, the temperature control box, the force sensor, the lower pressure head mechanism, the upper pressure head mechanism, the beam and the displacement testing mechanism are all disposed in an inner cavity of the frame, the bottom of the force sensor is abutted to the bottom of the inner cavity of the frame, and the beam is slidably connected to a side wall of the inner cavity of the frame.
3. The non-thermal steady state mechanical testing device based on the mechanical difference method as claimed in claim 1, wherein the lower pressure head mechanism comprises a lower base, a lower pipe body, a lower pressure head seat and a lower pressure head which are coaxially arranged along the vertical direction;
the bottom of the lower base is connected with the force sensor, the lower pipe body is fixedly arranged in an inner cavity at the top of the lower base, the top of the lower pipe body is connected with the bottom of the lower pressure head seat in an embedded mode, and the lower pressure head is embedded in the top of the lower pressure head seat;
the lower base is provided with a first water-cooling channel, and the inner cavity of the lower tube body is communicated with an external water-cooling device through the first water-cooling channel.
4. The non-thermal steady state mechanical testing device based on the mechanical difference method as claimed in claim 3, wherein the upper pressure head mechanism comprises an upper base, an upper pipe body, an upper pressure head seat and an upper pressure head which are coaxially arranged along the vertical direction;
the top of the upper base is connected with the bottom of the cross beam, the upper pipe body is fixedly arranged in a bottom inner cavity of the upper base, the bottom of the upper pipe body is connected with the top of the upper pressure head seat in an embedded mode, the upper pressure head is embedded in the bottom of the upper pressure head seat, a gap for accommodating a sample to be detected is reserved between the upper pressure head and the lower pressure head, and the distance between the upper surface of the lower pressure head and the lower surface of the upper pressure head is the displacement data of the sample to be detected;
the upper base is provided with a second water-cooling channel, and the inner cavity of the upper pipe body is communicated with an external water-cooling device through the second water-cooling channel.
5. The mechanical difference method-based non-thermal steady-state mechanical testing device as claimed in claim 4, wherein the displacement testing mechanism comprises a sensor fixing member, a displacement sensor, a first differential rod, a second differential rod and a temperature-varying compensation rod;
the bottom of the sensor fixing piece is connected with the top of the cross beam, the displacement sensor is embedded in an inner cavity of the sensor fixing piece, and the first differential rod and the second differential rod are arranged in the vertical direction;
one end of the first differential rod is connected with the sensor fixing piece, and the other end of the first differential rod penetrates through the cross beam, the upper base and the upper pipe body in sequence and then is connected with the upper pressure head;
one end of the second differential rod is connected with the displacement sensor, the other end of the second differential rod penetrates through the cross beam, the upper base and the upper pipe body in sequence and then is coaxially connected with the variable temperature compensation rod, and one end, far away from the second differential rod, of the variable temperature compensation rod is abutted to the lower pressure head.
6. The mechanical differential method-based non-thermal steady-state mechanical testing device as claimed in claim 5, wherein the first differential rod and the second differential rod are made of rigid materials with the same thermal expansion coefficient;
when the temperature changes, the upper pressure head and the variable temperature compensation rod meet the following requirements:
L1/ L2=α2/α1
wherein L is1Is the initial length of the upper ram, alpha1Is the coefficient of thermal expansion, L, of the upper ram2Is the initial length, alpha, of the temperature change compensation rod2The thermal expansion coefficient of the temperature-changing compensation rod is shown.
7. An application method of the non-thermal steady-state mechanical testing device based on the mechanical difference method as claimed in any one of claims 1 to 6, characterized by comprising the following steps:
and synchronously acquiring temperature data, stress data and displacement data, controlling the temperature of the temperature control box or the position of the cross beam to keep any one of the data constant, and acquiring the relation between the other two data.
8. The method for applying the non-thermal steady-state mechanical testing device based on the mechanical difference method according to claim 7, wherein the testing step when the temperature data is constant comprises:
controlling the temperature of the temperature control box, applying the same constant temperature conditions to the lower pressure head, the upper pressure head and the sample to be measured, acquiring stress data by a force sensor, and acquiring displacement data by a displacement sensor;
and drawing a displacement-mechanical curve by combining the stress data and the displacement data, wherein the displacement-mechanical curve is the relation between the stress and the displacement of the sample to be measured when the temperature data is constant.
9. The method for applying the non-thermal steady-state mechanical testing device based on the mechanical difference method according to claim 7, wherein the testing step when the displacement data is constant comprises:
controlling the temperature of the temperature control box, applying the same temperature change condition to the lower pressure head, the upper pressure head and the sample to be measured, acquiring stress data by a force sensor, acquiring displacement data by a displacement sensor, and controlling the position of the cross beam to keep the displacement data constant in the temperature change process;
and drawing a temperature-mechanical curve by combining the temperature data and the stress data, wherein the temperature-mechanical curve is the relation between the temperature and the stress of the sample to be measured when the displacement data is constant.
10. The method for applying the non-thermal steady-state mechanical testing device based on the mechanical difference method according to claim 7, wherein the testing step when the stress data is constant comprises:
controlling the temperature of the temperature control box, applying the same temperature change condition to the lower pressure head, the upper pressure head and the sample to be measured, acquiring stress data by a force sensor, controlling the position of the cross beam to keep the stress data constant in the temperature change process, and acquiring displacement data by a displacement sensor;
and drawing a temperature-displacement curve by combining the temperature data and the displacement data, wherein the temperature-displacement curve is the relation between the temperature and the displacement of the sample to be measured when the stress data is constant.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111586239.8A CN113984543B (en) | 2021-12-23 | 2021-12-23 | Non-thermal steady state mechanical testing device based on mechanical difference method and application method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111586239.8A CN113984543B (en) | 2021-12-23 | 2021-12-23 | Non-thermal steady state mechanical testing device based on mechanical difference method and application method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113984543A true CN113984543A (en) | 2022-01-28 |
| CN113984543B CN113984543B (en) | 2022-05-17 |
Family
ID=79734103
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111586239.8A Active CN113984543B (en) | 2021-12-23 | 2021-12-23 | Non-thermal steady state mechanical testing device based on mechanical difference method and application method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113984543B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116660309A (en) * | 2023-07-31 | 2023-08-29 | 德阳市重装检测有限责任公司 | Device and method for measuring thermal-cold deformation performance of material in real time |
| CN116794092A (en) * | 2023-07-10 | 2023-09-22 | 青岛理工大学 | Rock damage quantification device and method in hot-cold alternating process |
Citations (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2192033Y (en) * | 1994-02-18 | 1995-03-15 | 上海钢铁研究所 | Device for measuring deformation generated by temp. |
| CN101526339A (en) * | 2009-04-22 | 2009-09-09 | 东南大学 | Temperature self-compensation fiber grating displacement sensor |
| CN102062571A (en) * | 2009-11-13 | 2011-05-18 | 上海华龙测试仪器有限公司 | Device for enhancing test accuracy of large-deformation extensometer |
| CN104316404A (en) * | 2014-11-03 | 2015-01-28 | 中国航空工业集团公司北京航空材料研究院 | Accurate measurement method for resilience of memory alloy |
| CN205607369U (en) * | 2016-04-12 | 2016-09-28 | 深圳市万泽中南研究院有限公司 | High -temperature extensometer |
| CN106226347A (en) * | 2016-08-17 | 2016-12-14 | 中钢集团洛阳耐火材料研究院有限公司 | A kind of displacement measurement system of the vertical high temperature thermal dilatometer |
| CN106525603A (en) * | 2016-12-07 | 2017-03-22 | 金堆城钼业股份有限公司 | Molybdenum and molybdenum alloy bar/tube high-temperature tensile detection device and method |
| CN106969701A (en) * | 2017-04-10 | 2017-07-21 | 广西交通科学研究院有限公司 | The modification method that temperature influences in strain testing |
| US20180238785A1 (en) * | 2017-02-17 | 2018-08-23 | Ut-Battelle, Llc | Molten salt environment creep testing extensometry system |
| CN109470558A (en) * | 2018-12-19 | 2019-03-15 | 中国科学院地球化学研究所 | A kind of calibration device for displacement sensor under high temperature and pressure |
| CN109696362A (en) * | 2018-12-20 | 2019-04-30 | 航天特种材料及工艺技术研究所 | A kind of mechanical stretch performance testing device and test method under hot environment |
| CN109932252A (en) * | 2019-03-20 | 2019-06-25 | 大连理工大学 | A kind of current vortex heating high-temperature mechanics test device |
| CN111198131A (en) * | 2019-12-04 | 2020-05-26 | 西安航天三沃机电设备有限责任公司 | Measuring device and measuring method for volume expansion characteristic of material under tensile load |
| WO2020201656A1 (en) * | 2019-03-29 | 2020-10-08 | Acoem France | Apparatus for measuring properties of materials with improved precision by using laser sensors |
-
2021
- 2021-12-23 CN CN202111586239.8A patent/CN113984543B/en active Active
Patent Citations (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2192033Y (en) * | 1994-02-18 | 1995-03-15 | 上海钢铁研究所 | Device for measuring deformation generated by temp. |
| CN101526339A (en) * | 2009-04-22 | 2009-09-09 | 东南大学 | Temperature self-compensation fiber grating displacement sensor |
| CN102062571A (en) * | 2009-11-13 | 2011-05-18 | 上海华龙测试仪器有限公司 | Device for enhancing test accuracy of large-deformation extensometer |
| CN104316404A (en) * | 2014-11-03 | 2015-01-28 | 中国航空工业集团公司北京航空材料研究院 | Accurate measurement method for resilience of memory alloy |
| CN205607369U (en) * | 2016-04-12 | 2016-09-28 | 深圳市万泽中南研究院有限公司 | High -temperature extensometer |
| CN106226347A (en) * | 2016-08-17 | 2016-12-14 | 中钢集团洛阳耐火材料研究院有限公司 | A kind of displacement measurement system of the vertical high temperature thermal dilatometer |
| CN106525603A (en) * | 2016-12-07 | 2017-03-22 | 金堆城钼业股份有限公司 | Molybdenum and molybdenum alloy bar/tube high-temperature tensile detection device and method |
| US20180238785A1 (en) * | 2017-02-17 | 2018-08-23 | Ut-Battelle, Llc | Molten salt environment creep testing extensometry system |
| CN106969701A (en) * | 2017-04-10 | 2017-07-21 | 广西交通科学研究院有限公司 | The modification method that temperature influences in strain testing |
| CN109470558A (en) * | 2018-12-19 | 2019-03-15 | 中国科学院地球化学研究所 | A kind of calibration device for displacement sensor under high temperature and pressure |
| CN109696362A (en) * | 2018-12-20 | 2019-04-30 | 航天特种材料及工艺技术研究所 | A kind of mechanical stretch performance testing device and test method under hot environment |
| CN109932252A (en) * | 2019-03-20 | 2019-06-25 | 大连理工大学 | A kind of current vortex heating high-temperature mechanics test device |
| WO2020201656A1 (en) * | 2019-03-29 | 2020-10-08 | Acoem France | Apparatus for measuring properties of materials with improved precision by using laser sensors |
| CN111198131A (en) * | 2019-12-04 | 2020-05-26 | 西安航天三沃机电设备有限责任公司 | Measuring device and measuring method for volume expansion characteristic of material under tensile load |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116794092A (en) * | 2023-07-10 | 2023-09-22 | 青岛理工大学 | Rock damage quantification device and method in hot-cold alternating process |
| CN116794092B (en) * | 2023-07-10 | 2024-02-06 | 青岛理工大学 | Rock damage quantification device and method in hot-cold alternating process |
| CN116660309A (en) * | 2023-07-31 | 2023-08-29 | 德阳市重装检测有限责任公司 | Device and method for measuring thermal-cold deformation performance of material in real time |
| CN116660309B (en) * | 2023-07-31 | 2023-10-03 | 德阳市重装检测有限责任公司 | Method for measuring thermal-cold deformation performance of material in real time |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113984543B (en) | 2022-05-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113984543B (en) | Non-thermal steady state mechanical testing device based on mechanical difference method and application method thereof | |
| CN102589984A (en) | Multi-field coupled loading micro nanometer press-in testing system and method | |
| CN105572027B (en) | Concrete cracking whole process simulation testing machine | |
| CN104215521B (en) | Re-power-environment coupled action test device and application under room temperature to superhigh temperature | |
| CN110044752A (en) | High/low temperature impression test device in situ for cone-beam CT imaging | |
| CN112858033A (en) | Electric heating shape memory alloy spring performance test system | |
| CN106705926A (en) | Static standard strain loading device based on simply-supported pure bending beam and method thereof | |
| GB2286047A (en) | Extensometer and support for an extensometer | |
| CN105403466B (en) | A kind of in situ quantitation power thermal coupling tensile test apparatus for ultramicroscope | |
| Mates et al. | A pulse-heated Kolsky bar technique for measuring the flow stress of metals at high loading and heating rates | |
| US4687343A (en) | Deformation dilatometer platens | |
| JP4062383B2 (en) | Compression creep testing machine | |
| Du et al. | Force sensors embedded in surfaces for manufacturing and other tribological process monitoring | |
| Guo et al. | Development in optical methods for reliability analysis in electronic packaging applications | |
| CN104198663B (en) | Indentation system and the method for many coupling performances of a kind of material total temperature section | |
| US7395722B2 (en) | Mechanical property measurement of thin films by micro plane-strain compression | |
| Oh et al. | Techniques for measuring thermal expansion and creep of polysilicon | |
| JP2000214058A (en) | Method and device for creep test | |
| CN207636528U (en) | Linear expansion coefficient detection device | |
| CN107621475A (en) | A kind of thermal coefficient of expansion high pass amount detecting device and its control method | |
| CN111829946A (en) | Carbon fiber prepreg friction coefficient measuring device and using method thereof | |
| JP2780826B2 (en) | Thermal fatigue test method | |
| CN105699619A (en) | Metal thermal electromotive force measuring instrument | |
| CN110057657A (en) | A kind of sample stress bringing device | |
| JP4385520B2 (en) | High temperature hardness tester |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |