CN115773930A - Uncertainty evaluation method for room temperature tensile test result of aviation material - Google Patents
Uncertainty evaluation method for room temperature tensile test result of aviation material Download PDFInfo
- Publication number
- CN115773930A CN115773930A CN202111049496.8A CN202111049496A CN115773930A CN 115773930 A CN115773930 A CN 115773930A CN 202111049496 A CN202111049496 A CN 202111049496A CN 115773930 A CN115773930 A CN 115773930A
- Authority
- CN
- China
- Prior art keywords
- uncertainty
- tensile test
- test
- room temperature
- temperature tensile
- 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.)
- Pending
Links
- 238000009864 tensile test Methods 0.000 title claims abstract description 40
- 239000000463 material Substances 0.000 title claims abstract description 22
- 238000011156 evaluation Methods 0.000 title claims abstract description 20
- 238000005259 measurement Methods 0.000 claims abstract description 46
- 238000004364 calculation method Methods 0.000 claims abstract description 11
- 238000012360 testing method Methods 0.000 claims description 41
- 238000000034 method Methods 0.000 claims description 23
- 239000011825 aerospace material Substances 0.000 claims description 9
- 229910001069 Ti alloy Inorganic materials 0.000 claims description 4
- 238000013178 mathematical model Methods 0.000 abstract description 6
- 238000013461 design Methods 0.000 description 3
- 238000010146 3D printing Methods 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000011157 data evaluation Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000012854 evaluation process Methods 0.000 description 1
- 230000014509 gene expression Effects 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012797 qualification Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000009897 systematic effect Effects 0.000 description 1
Images
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P90/00—Enabling technologies with a potential contribution to greenhouse gas [GHG] emissions mitigation
- Y02P90/30—Computing systems specially adapted for manufacturing
Landscapes
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
The disclosure relates to an uncertainty evaluation method for room temperature tensile test result of aviation material, which comprises the following steps of calculating the uncertainty of the measurement of the tensile strength:and/or, calculating a dimensional measurement uncertainty of yield strength:by applying Taylor formula to expand a mathematical model considering yield strength and tensile strength and neglecting second-order small quantity, a calculation method of dimensional measurement uncertainty is obtained, uncertainty generated on a room-temperature tensile test result, which is introduced by a sample in an original state and a failure state due to human factors, is quantitatively evaluated, evaluation accuracy is high, and high feasibility is achieved.
Description
Technical Field
The disclosure relates to an uncertainty evaluation method for room temperature tensile test results of an aviation material.
Background
The statements herein merely provide background information related to the present disclosure and may not necessarily constitute prior art.
The room temperature tensile test result of the aviation material mainly comprises mechanical properties such as yield strength, tensile strength and the like. The testing result of the test sample obtained by the testing machine is only an estimated value of the measured parameter, and a plurality of random factors and system effects exist in the testing process, which can cause uncertainty of the testing result. Regardless of the perfection of various factors such as testing personnel, instruments and equipment, method standards, environmental conditions and the like, the test result of the measured parameter has uncertainty. For a sample whose acceptability needs to be determined, the uncertainty of the test result around the design allowable value has a great influence on the determination of the acceptability of the product. For 3D printing aviation materials, the current domestic and foreign related detection standards have certain requirements on uncertainty evaluation of room temperature tensile tests, but no complete scheme is provided for evaluation, and the problems of insufficient consideration of uncertainty influence factors of the room temperature tensile tests, lack of aviation materials, particularly a performance data evaluation method of the 3D printing aviation materials and the like exist.
Disclosure of Invention
One technical problem to be solved by the present disclosure is: the method for evaluating the uncertainty of the room temperature tensile test result of the aviation material can improve the evaluation accuracy of the uncertainty of the room temperature tensile test result of the aviation material.
Some embodiments of the present disclosure provide a method for evaluating uncertainty of room temperature tensile test results of an aerospace material, including:
calculate the dimensional measurement uncertainty of tensile strength:
and/or
Calculating the dimensional measurement uncertainty of yield strength:
wherein,dimensional measurement for tensile strengthUncertainty; r is m Is the tensile strength of the specimen;to measure tool uncertainty; d 0 Measuring the size of the sample;measuring uncertainty for the size of the yield strength; r is 0.2 The yield strength of the test specimen.
In some embodiments, further comprising: the multiple specimens were individually subjected to a tensile test and dimensional measurement uncertainty was calculated until the calculated values converged.
In some embodiments, the plurality of specimens comprises a plurality of specimens of different batches, performing the tensile test on the plurality of specimens individually and calculating the dimensional measurement uncertainty comprises: firstly, carrying out tensile test on different samples of the same batch one by one and calculating the uncertainty of dimension measurement, and then carrying out tensile test on different samples of another batch one by one and calculating the uncertainty of dimension measurement.
In some embodiments, the calculated sample number of specimens is configured as 100 pieces.
In some embodiments, the coupon comprises a titanium alloy coupon or a 3D printed aerospace material.
In some embodiments, further comprising:
calculating the uncertainty of repeated measurement;
obtaining uncertainty of test load; and
and taking an arithmetic mean root of the sum of squares of the dimensional measurement uncertainty, the repeated measurement uncertainty and the test load uncertainty to obtain the synthetic uncertainty.
In some embodiments, the repeated measurement uncertainty is obtained by statistical calculations and the test load uncertainty is obtained by certification/calibration of the equipment.
In some embodiments, further comprising: the extension uncertainty was calculated with a confidence probability of 95%.
According to the technical scheme, the calculation method of the dimensional measurement uncertainty is obtained by applying the Taylor formula to expand the mathematical model considering the yield strength and the tensile strength and neglecting the second-order small quantity, the uncertainty of the room-temperature tensile test result, which is caused by the fact that the sample is introduced in the original state and the failure state due to human factors, is quantitatively evaluated, the evaluation accuracy is high, and the method has high feasibility.
Drawings
In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the drawings used in the embodiments or the prior art descriptions will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present disclosure, and other drawings can be obtained by those skilled in the art without creative efforts.
FIG. 1 is a graph of experimental data distribution of yield strength according to some embodiments of the disclosed method for uncertainty evaluation of room temperature tensile test results for aerospace materials;
fig. 2 is a graph of experimental data distribution for tensile strength according to some embodiments of the disclosed method for uncertainty evaluation of room temperature tensile test results for aerospace materials.
Detailed Description
Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. The description of the exemplary embodiments is merely illustrative and is in no way intended to limit the disclosure, its application, or uses. The present disclosure may be embodied in many different forms and is not limited to the embodiments herein. These embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. It should be noted that: the relative arrangement of parts and steps, the composition of materials, numerical expressions and numerical values set forth in these embodiments are to be construed as merely illustrative, and not as limitative, unless specifically stated otherwise.
The use of "first," "second," and similar terms in this disclosure is not intended to indicate any order, quantity, or importance, but rather are used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element preceding the word comprises the element listed after the word, and does not exclude the possibility that other elements may also be included. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.
In the present disclosure, when a specific device is described as being located between a first device and a second device, there may or may not be intervening devices between the specific device and the first device or the second device. When a particular device is described as being coupled to other devices, the particular device may be directly coupled to the other devices without intervening devices or may be directly coupled to the other devices with intervening devices.
All terms used in the present disclosure have the same meaning as understood by one of ordinary skill in the art to which the present disclosure belongs, unless otherwise specifically defined. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail, but are intended to be part of the specification where appropriate.
According to some embodiments of the present disclosure, a method for evaluating uncertainty of room temperature tensile test result of an aeronautical material is provided, which includes:
calculate the dimensional measurement uncertainty of tensile strength:
and/or
Calculating the dimensional measurement uncertainty of yield strength:
wherein,measuring uncertainty for the dimensions of the tensile strength; r is m Is the tensile strength of the specimen;to measure tool uncertainty; d is a radical of 0 Measuring the size of the sample;measuring uncertainty for the size of the yield strength; r is 0.2 The yield strength of the test specimen.
The problems of test invalidation and the like are mainly caused by the fact that test results or parameters are greatly inconsistent, and the uncertainty is mainly caused by the fact that a part of parameters introduce small changes in the test process and is usually far lower than the magnitude order of the original test parameters (the size grade of a sample is in a decimeter scale, and the uncertainty of measuring equipment such as a vernier caliper is 0.02 mm). When the room temperature tensile test is carried out, the test result has certain uncertainty due to systematic errors and human factors, the independent variable is usually negligible relative to the basic parameters and the test result of the test, but the research caused by numerical value fluctuation around the design allowable value is indispensable.
The present disclosure therefore calculates the dimensional measurement uncertainty of the test specimen by considering the taylor expansion formula, the measured value of the dimension being mainly concentrated at the denominator of the mathematical model, e.g., tensile strength (MPa) as load (kN) and cross-sectional area (mm) of the test specimen 2 ) The ratio of (a) to (b). Thus selecting (1-x) -1 By the expansion of (1-x) -1 The expansion, as x approaches 0, is of the form:
(1-x) -1 =1-x+R 1 (x)
since the measurement uncertainty itself is a very small quantity in the measurement process, the ratio of this value to the measured estimated value can be regarded as a substantially constant value approaching 0, and the second order small quantity and the subsequent remainder are ignored. After applying the taylor formula expansion and ignoring the second order small quantities by considering the mathematical model of yield strength, a calculation method of the uncertainty introduced due to the dimensional measurement can be obtained:
the mathematical model of tensile strength in tensile test is as follows: r m =F m /S 0 In the formula, R m Denotes tensile strength, F m Represents the maximum value of the load during the test, S 0 Representing the original cross-sectional area of the sample to be tested.
After applying taylor's formula expansion and ignoring the second order small quantity, one can get:
therefore, the dimensional measurement uncertainty of tensile strength:
similarly, the dimensional measurement uncertainty of yield strength:
the calculation method of the dimensional measurement uncertainty is obtained by applying a Taylor formula to a mathematical model considering yield strength and tensile strength and expanding and neglecting second-order small quantity, the requirement of the uncertainty evaluation process on the quantity of aviation material performance data is greatly reduced, the cost is reduced to a certain extent, and the efficiency is improved, so that the uncertainty of a room-temperature tensile test result, which is introduced by a sample in an original state and a failure state due to human factors, is quantitatively evaluated, the evaluation accuracy is high, and the method has high practicability.
As shown in conjunction with fig. 1 and 2, in some embodiments, the method further comprises: the multiple specimens were individually subjected to a tensile test and dimensional measurement uncertainty was calculated until the calculated values converged. And (3) performing structured storage on the performance data of the aviation materials in the same batch, uniformly evaluating the uncertainty after obtaining samples of the same batch but different part numbers, continuously increasing the number of samples after continuing the test, and dynamically calculating until the calculated value is converged. After the dynamic calculation uncertainty value is converged, the process that the test result is repeatedly introduced into the calculation can be greatly reduced, and various costs caused by repeated tests are reduced to a certain extent.
In some embodiments, the plurality of specimens comprises a plurality of specimens from different batches, and performing the tensile test on the plurality of specimens individually and calculating the dimensional measurement uncertainty comprises: firstly, carrying out tensile test on different samples of the same batch one by one and calculating the uncertainty of dimension measurement, and then carrying out tensile test on different samples of another batch one by one and calculating the uncertainty of dimension measurement. After the room-temperature tensile test is completed each time, test data and the previous tensile samples in the same batch are gathered, and uncertainty of evaluation and calculation is evaluated, so that the problems of over-conservative evaluation and the like are avoided.
In some embodiments, the calculated sample number of specimens is configured as 100 pieces to ensure test accuracy.
In some embodiments, the specimens comprise titanium alloy specimens or 3D printed aerospace materials, and the evaluation methods of the present disclosure are particularly useful for evaluating titanium alloy specimens or 3D printed aerospace materials.
In some embodiments, the method further comprises:
calculating the uncertainty of repeated measurement;
obtaining uncertainty of the test load; and
and taking an arithmetic mean root of the sum of squares of the dimensional measurement uncertainty, the repeated measurement uncertainty and the test load uncertainty to obtain the composite uncertainty.
It should be noted that, herein, dimensional measurement uncertainty refers to uncertainty introduced by dimensional measurement; the repeated measurement uncertainty refers to uncertainty introduced by repeated measurement; test load uncertainty refers to the uncertainty introduced by the test load. The repeated measurement uncertainty is obtained by statistical calculation, and the test load uncertainty is obtained by a certification/calibration certificate of the equipment.
To obtain the extension uncertainty, in some embodiments, the method further comprises: the extended uncertainty was calculated with a confidence probability of 95%.
The invention provides a technical idea for judging the qualification of a measured value of a test result near a design allowable value, and fills up the uncertainty evaluation method of an aviation material in the field of room-temperature tensile test by designing a flow for dynamically evaluating uncertainty, so that the requirement of the material on performance data accumulation in the aspect of uncertainty evaluation is reduced, and the subsequent calculation is more convenient.
Thus far, various embodiments of the present disclosure have been described in detail. Some details well known in the art have not been described in order to avoid obscuring the concepts of the present disclosure. Those skilled in the art can now fully appreciate how to implement the teachings disclosed herein, in view of the foregoing description.
Although some specific embodiments of the present disclosure have been described in detail by way of example, it should be understood by those skilled in the art that the foregoing examples are for purposes of illustration only and are not intended to limit the scope of the present disclosure. It will be understood by those skilled in the art that various changes may be made in the above embodiments or equivalents may be substituted for elements thereof without departing from the scope and spirit of the present disclosure. The scope of the present disclosure is defined by the appended claims.
Claims (8)
1. An uncertainty evaluation method for room temperature tensile test results of aviation materials comprises the following steps:
calculate the dimensional measurement uncertainty of tensile strength:
and/or
Calculating the dimensional measurement uncertainty of yield strength:
2. The method for evaluating the uncertainty of the room temperature tensile test result of the aircraft material according to claim 1, further comprising: the multiple specimens were individually subjected to a tensile test and dimensional measurement uncertainty was calculated until the calculated values converged.
3. The aircraft material room temperature tensile test result uncertainty evaluation method according to claim 2, wherein the plurality of specimens includes a plurality of specimens of different batches, and the performing the tensile test on the plurality of specimens one by one and calculating the dimensional measurement uncertainty includes: firstly, carrying out tensile test on different samples of the same batch one by one and calculating the uncertainty of dimension measurement, and then carrying out tensile test on different samples of another batch one by one and calculating the uncertainty of dimension measurement.
4. The uncertainty evaluation method of the result of the room temperature tensile test of an aircraft material according to claim 1, wherein the number of the calculated samples of the test pieces is configured to be 100 pieces.
5. The method for evaluating uncertainty in the result of a room temperature tensile test of an aerospace material as claimed in claim 1, wherein the test sample comprises a titanium alloy test sample or a 3D printed aerospace material.
6. The method for evaluating uncertainty in the result of a room temperature tensile test of an aerospace material as claimed in claim 1, further comprising:
calculating the uncertainty of repeated measurement;
obtaining uncertainty of the test load; and
and taking an arithmetic mean root of the sum of squares of the dimensional measurement uncertainty, the repeated measurement uncertainty and the test load uncertainty to obtain the synthetic uncertainty.
7. The method for evaluating uncertainty of result of room temperature tensile test of aircraft material according to claim 6, wherein the repeated measurement uncertainty is obtained by statistical calculation, and the test load uncertainty is obtained by certification/calibration of equipment.
8. The method for evaluating the uncertainty of the room temperature tensile test result of the aircraft material according to claim 6, further comprising: the extension uncertainty was calculated with a confidence probability of 95%.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202111049496.8A CN115773930A (en) | 2021-09-08 | 2021-09-08 | Uncertainty evaluation method for room temperature tensile test result of aviation material |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202111049496.8A CN115773930A (en) | 2021-09-08 | 2021-09-08 | Uncertainty evaluation method for room temperature tensile test result of aviation material |
Publications (1)
Publication Number | Publication Date |
---|---|
CN115773930A true CN115773930A (en) | 2023-03-10 |
Family
ID=85388020
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202111049496.8A Pending CN115773930A (en) | 2021-09-08 | 2021-09-08 | Uncertainty evaluation method for room temperature tensile test result of aviation material |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN115773930A (en) |
-
2021
- 2021-09-08 CN CN202111049496.8A patent/CN115773930A/en active Pending
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Motra et al. | Assessment of strain measurement techniques to characterise mechanical properties of structural steel | |
CN111339700B (en) | Method and device for evaluating fatigue damage of nuclear turbine blade and storage medium | |
Schweitz et al. | Evaluation of mechanical materials properties by means of surface micromachined structures | |
CN106021685B (en) | A kind of Degradation Reliability analysis method considering measurement error | |
CN105092374A (en) | Test method suitable for elastic modulus of coated fabric membrane material in model test | |
CN108593964B (en) | Calibration method of seven-hole airflow probe | |
CN106644712A (en) | Testing method for automatically measuring thickness thinning rate by adopting tensile testing machine | |
CN108548720A (en) | The method that I type crackle elastic plastic theory formula obtain ductile material J resistance curves | |
CN107101800B (en) | Wind power measuring equipment and method for power transmission iron tower model | |
CN115773930A (en) | Uncertainty evaluation method for room temperature tensile test result of aviation material | |
CN109490334B (en) | Nondestructive testing method for T-shaped forge piece by using residual stress prediction model | |
CN101592692B (en) | Evaluation method of measuring machines | |
CN116187053A (en) | Method and device for measuring uncertainty of arm support stress based on Monte Carlo method | |
Pástor et al. | Possibility of using of tensometry in deformation analysis in areas with sudden change of geometry | |
Dally | 11. Statistical Statistical Analysis of Experimental Data | |
CN105675421A (en) | GH4145 bolt Brinell hardness value determination method and apparatus | |
CN104407222A (en) | Method for measuring electrical resistivity of irregular small-section copper bar material | |
KR102230397B1 (en) | Displacement Estimating Method of a Structure based on Acceleration and Strain | |
Dhawale et al. | Evaluating measurement capabilities by gauge R&R using ANOVA for reliability | |
CN105675417A (en) | GH4145 bolt Rockwell hardness value determination method and apparatus | |
CN111780695B (en) | Method for evaluating CT size measurement accuracy by DVC deformation algorithm | |
Vladimír et al. | The methodology of transformation of the nominal loading process into a root of notch | |
CN106323222B (en) | A kind of measurement method for the wide deformation of crack rock gap | |
Tokarska et al. | Determination of woven fabric impact permeability index | |
Prakken | 3D Printed flow sensor |
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 |