CN109434570B - Microbeam plasma polishing device and method for curved metal parts - Google Patents
Microbeam plasma polishing device and method for curved metal parts Download PDFInfo
- Publication number
- CN109434570B CN109434570B CN201811407444.1A CN201811407444A CN109434570B CN 109434570 B CN109434570 B CN 109434570B CN 201811407444 A CN201811407444 A CN 201811407444A CN 109434570 B CN109434570 B CN 109434570B
- Authority
- CN
- China
- Prior art keywords
- polishing
- polished
- metal part
- curved
- plasma
- 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.)
- Active
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B1/00—Processes of grinding or polishing; Use of auxiliary equipment in connection with such processes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B41/00—Component parts such as frames, beds, carriages, headstocks
- B24B41/06—Work supports, e.g. adjustable steadies
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B55/00—Safety devices for grinding or polishing machines; Accessories fitted to grinding or polishing machines for keeping tools or parts of the machine in good working condition
- B24B55/04—Protective covers for the grinding wheel
-
- 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
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/10—Greenhouse gas [GHG] capture, material saving, heat recovery or other energy efficient measures, e.g. motor control, characterised by manufacturing processes, e.g. for rolling metal or metal working
Abstract
The invention belongs to the technical field related to surface finish machining of metal materials, and discloses a microbeam plasma polishing device and a microbeam plasma polishing method for curved metal parts, wherein the microbeam plasma polishing device comprises a control assembly, a surface contour detector, a linkage mechanism, a plasma processing gun and a part clamp, the surface contour detector and the linkage mechanism are respectively connected with the control assembly, and the part clamp is arranged on the linkage mechanism; the plasma processing gun is connected with the control assembly; when the previous polishing is finished, the control component calculates the optimal polishing parameters of the strip-shaped convex stripes generated at the lap joint of the previous polishing scanning according to the surface morphology of the polished area of the curved metal part; thereafter, the control assembly controls the movement of the linkage mechanism according to the optimal polishing parameters to polish the metal part with the curved surface to be polished next time, thereby covering the strip-shaped raised stripes. The invention improves the quality and the polishing efficiency of the curved polishing surface and is convenient to use.
Description
Technical Field
The invention belongs to the technical field related to surface finish machining of metal materials, and particularly relates to a microbeam plasma polishing device and method for curved-surface metal parts.
Background
With the increasing demands on the quality, running costs and versatility of polished products, in order to obtain a workpiece with acceptable surface roughness, the surface thereof needs to be polished in the final step of workpiece preparation. Polishing refers to a machining process that reduces the surface roughness of a workpiece to obtain a bright, flat surface. Conventional polishing methods utilize a polishing tool and abrasive particles or other polishing media to precisely machine the surface of a workpiece. Under the prior art, the common polishing machine can process simple molded surfaces such as planes, cannot process curved surfaces, easily generates polishing marks, and has uneven polishing and poor polishing effect, so that the need for a new curved surface finish machining method is urgent.
Currently, plasma beams have been successfully applied to planar polishing of metals, utilizing ionization of high purity Ar gas, to form a plasma arc between a discharge tungsten electrode and the surface of an anode material. Under the action of high-energy density beam current of plasma arc, the metal on the surface layer of the material reaches the melting point and melts, and as the surface to be treated is rugged, the raised peak tip of the rough surface is melted by heating first, and under the action of self gravity and surface tension, molten liquid flows to the concave position first to fill gaps, and then solidifies rapidly, so that a smooth and bright acting surface is finally obtained.
The influence of the gravity of the liquid molten pool and the surface tension is the key point for realizing the surface smoothness, on one hand, if the gravity direction of the liquid pool and the normal direction of a curved surface form an included angle, the gravity of the liquid pool can guide the liquid phase to flow downwards, on the other hand, the surface tension is influenced by the temperature gradient, and if the two sides of the liquid pool are heated inconsistently, the asymmetric flow of the liquid phase in the liquid pool is caused, so that the balance of the gravity and the temperature gradient at the two sides of a single track is grasped, the core principle of micro-beam plasma polishing of a curved surface metal part is realized, the metal surface morphology after micro-fusion is directly influenced, and the balance of the gravity balance of the liquid pool and the temperature gradient at the two sides of the liquid pool is more difficult to keep when the high-energy beam acts on the curved surface than when the high-energy beam acts on the plane. In addition, in the plasma beam polishing process, the liquid metal in the molten pool forms axisymmetric circulation under the combined action of surface tension and thermal capillary force, the liquid metal in the middle part of the molten pool reaches the boundary and solidifies under the circulation action, microprotrusions on two sides of a molten channel are formed, and the larger the heat input of the plasma arc is, the more obvious the protrusions are. Thus, although the local roughness in the middle of the molten pool is low, the roughness cannot be reduced to an optimal state for the whole polished surface. Accordingly, there is a need in the art to develop a microbeam plasma polishing apparatus and method for curved metal parts with better polishing quality.
Disclosure of Invention
Aiming at the defects or improvement demands of the prior art, the invention provides a microbeam plasma polishing device and a microbeam plasma polishing method for a curved metal part, which are based on the polishing characteristics of the curved metal part, and are simple to use and good in polishing quality. The polishing device is used for carrying out next scanning at the lap joint based on previous plasma scanning, and takes the optimal polishing parameters capable of covering the strip-shaped raised stripes generated at the lap joint during previous polishing as the working parameters of next polishing, so that the strip-shaped raised stripes at the lap joint are polished for the next polishing until the required surface roughness is obtained, the efficiency and quality are improved, the applicability is higher, and the flexibility is better.
In order to achieve the above object, according to one aspect of the present invention, there is provided a microbeam plasma polishing apparatus for curved metal parts, the apparatus comprising a control assembly, a surface profile finder, a linkage mechanism, a gas protection cover, a plasma processing gun, a plasma gun fixing base, and a part holder, the surface profile finder being connected to the control assembly, the linkage mechanism being connected to the control assembly, the part holder being provided on the linkage mechanism, the part holder being for holding a curved metal part to be polished; the plasma processing gun is arranged on the plasma gun fixing base and is connected with the control assembly; the gas protection cover is covered outside the plasma processing gun;
after finishing the previous polishing, the surface profile detector measures the surface morphology of the current polishing area of the metal part with the curved surface to be polished, and transmits the obtained data to the control component, so that the control component calculates and obtains the optimal polishing parameters of the strip-shaped convex stripes generated at the scanning lap joint part when the previous polishing is covered according to the surface roughness and the profile line of the metal part with the curved surface to be polished; and then, the control assembly controls the linkage mechanism to drive the curved surface metal part to be polished to move relative to the plasma processing gun according to the optimal polishing parameters so as to polish the curved surface metal part to be polished for the next time, thereby covering the strip-shaped raised stripes.
Further, the control component is used for designing structural parameters of the pre-polished curved surface metal part according to the structure of the curved surface metal part to be polished, and simulating a microbeam plasma polishing process by utilizing a finite element numerical simulation analysis method, so that working parameters in the polishing process are determined.
Further, a plasma main arc is generated between the plasma processing gun and the curved metal part to be polished; generating a pilot arc in the plasma processing gun; the working parameters comprise the voltage and the current of a pilot arc; a current of the plasma main arc; the flow rate, the pre-delivery time and the lag time of the ionized gas and the shielding gas; muzzle height of the plasma processing gun; arc moving distance and curved surface rotation speed of the curved surface metal part to be polished.
Further, in the polishing process, the central axis of the plasma processing gun coincides with the normal line of the curved surface metal part to be polished at the polishing point.
Further, the single-pass polishing movement of the curved surface metal part to be polished relative to the plasma processing gun is self-rotation movement of the curved surface metal part to be polished around the central axis of the curved surface metal part to be polished; and the moving track of the rotary wheel starts from the center of the curved metal part to be polished during rotary polishing, and polishing is performed from inside to outside.
Further, the plasma processing gun comprises a copper nozzle and a tungsten needle arranged in the copper nozzle; the polishing device comprises an arc striking high-frequency power supply and a main arc direct current power supply which are respectively connected with the control assembly, and the anode and the cathode of the main arc direct current power supply are respectively connected with the curved surface metal part to be polished and the tungsten needle; and the negative electrode and the positive electrode of the arc striking high-frequency power supply are respectively connected with the tungsten needle and the copper nozzle.
Further, the polishing device further comprises an ionized gas cylinder, a protective gas cylinder and a flow controller, wherein the flow controller is connected to the control assembly, and the ionized gas cylinder and the protective gas cylinder are respectively connected with the plasma processing gun and the gas protection cover through the flow controller.
Further, the total input power used in the next scanning is smaller than that used in the last scanning, and the ratio of the single-channel width of the next scanning to the single-channel width of the last scanning is 1 (3-4).
According to another aspect of the present invention, there is provided a microbeam plasma polishing method for a curved metal part, the method comprising the steps of:
(1) Providing the microbeam plasma polishing device for the curved metal part, placing the curved metal part to be polished on the part clamp, and polishing the curved metal part to be polished for the first time by the polishing device;
(2) The surface profile detector measures the appearance of a polishing area of the metal part with the curved surface to be polished after the previous polishing, and transmits the measured data to the control component, and the control component calculates the optimal polishing parameters of the strip-shaped raised stripes generated at the scanning lap joint part during the covering of the previous polishing according to the structure of the metal part with the curved surface to be polished; the polishing device polishes the curved surface metal part to be polished for the next time according to the optimal polishing parameters;
(3) And (3) the surface profile detector measures the surface morphology of the metal material of the metal part with the curved surface to be polished, which is obtained in the step (2), and transmits the obtained data to the control component, so that the control component judges whether the surface roughness of the metal part with the curved surface to be polished meets the target requirement, if so, the polishing is finished, and otherwise, the step (2) is carried out.
Further, the flow rate of the shielding gas entering the gas shielding cover is 5L/min, the pre-feeding time is 10s, and the hysteresis time is 10s.
In general, compared with the prior art, the microbeam plasma polishing device and method for the curved metal parts, which are designed by the invention, have the following advantages:
1. the control component calculates and obtains optimal polishing parameters of the strip-shaped convex stripes generated at the scanning lap joint when the surface roughness and the contour line of the curved metal part to be polished are covered in the previous polishing process; and then, the control assembly controls the linkage mechanism to drive the curved surface metal part to be polished to move relative to the plasma processing gun according to the optimal polishing parameters so as to polish the curved surface metal part to be polished next time, thereby covering the strip-shaped raised stripes, improving the quality and the production efficiency of the polished surface, and being simple in structure and convenient to manufacture and use.
2. The protective gas is sent in advance and is lagged, so that the success of arcing can be ensured, and meanwhile, the oxidation of the surface of the metal material and the oxidation of a tungsten needle in the plasma processing gun can be continuously prevented after polishing contact.
3. The moving track of the rotary wheel starts from the center of the curved surface metal part to be polished during rotary polishing, polishing is performed from inside to outside, scale marks on a single track due to low substrate temperature and large temperature gradient are avoided, and polishing quality is improved.
4. The single-pass polishing movement of the curved surface metal part to be polished relative to the plasma processing gun is self-rotation movement of the curved surface metal part to be polished around the central axis of the curved surface metal part to be polished, so that the time required by a polishing procedure is saved, and the polishing efficiency is improved.
Drawings
Fig. 1 is a schematic view of a microbeam plasma polishing apparatus for curved metal parts according to the present invention in a use state.
Fig. 2 is a partial schematic view of the microbeam plasma polishing apparatus of the curved metal part of fig. 1 in another state of use.
Fig. 3 (a) and (b) are schematic views showing two effects of the central axis and the Z-axis angle of the plasma processing gun of the microbeam plasma polishing apparatus for curved metal parts in fig. 1 on the plasma arc morphology.
Fig. 4 is a partial cross-sectional view of a plasma processing gun of the microbeam plasma polishing apparatus of the curved metal part of fig. 1.
Fig. 5 is a schematic diagram of a linkage mechanism of the microbeam plasma polishing apparatus for curved metal parts in fig. 1.
Fig. 6A is a schematic view of a path taken by the microbeam plasma polishing apparatus of the curved metal part of fig. 1 for a first pass.
Fig. 6B is a partial cross-sectional view of the workpiece along the A-A direction of the beam plasma polishing apparatus of the curved metal part of fig. 1, scanned in accordance with the path of fig. 6A.
Fig. 7A is a schematic view of a path taken by the microbeam plasma polishing apparatus for the second pass of the curved metal part of fig. 1.
Fig. 7B is a partial cross-sectional view of the workpiece along the direction B-B of the microbeam plasma polishing apparatus of the curved metal part of fig. 1, scanned in accordance with the path of fig. 7A.
The same reference numbers are used throughout the drawings to reference like elements or structures, wherein:
the device comprises a 1-plasma processing gun, a 2-gas protection cover, a 3-plasma gun fixing base, a 4-ionized gas cylinder, a 5-protection gas cylinder, a 6-gas flow controller, a 7-striking high-frequency power supply, an 8-main arc direct current power supply, a 9-convex part to be polished, a 10-control component, a 11-part clamp, a 12-conductive working platform, a 13-linkage mechanism, a 14-surface profile detector, a 15-concave part to be polished, a 16-tungsten needle and a 17-copper nozzle.
Detailed Description
The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention. In addition, the technical features of the embodiments of the present invention described below may be combined with each other as long as they do not collide with each other.
Referring to fig. 1, 2, 3 and 4, the microbeam plasma polishing device for curved metal parts provided by the invention comprises a plasma processing gun 1, a gas protection cover 2, a plasma gun fixing base 3, an ionized gas bottle 4, a shielding gas bottle 5, a gas flow controller 6, an arc induction high-frequency power supply 7, a main arc direct current power supply 8, a control component 10, a part clamp 11, a conductive working platform 12, a linkage mechanism 13 and a surface profile detector 14, wherein the plasma processing gun 1 is connected to the plasma gun fixing base 3, the gas protection cover 2 is covered outside the plasma processing gun 1, and the central axis of the plasma processing gun 1 coincides with the central axis of the plasma gun fixing base 3. The plasma processing gun 1 is connected to the control assembly 10, and the control assembly 10 is used for controlling the plasma processing gun 1. The surface profile finder 14 is connected to the control assembly 10, the control assembly 10 is configured to control the surface profile finder 14 to measure a polishing area of a metal part with a curved surface to be polished in real time, the surface profile finder 14 also transmits measured data to the control assembly 10 in real time, and the control assembly 10 determines various optimal parameters in the polishing process according to the received data.
The gas flow controller 6, the arc striking high-frequency power supply 7, the main arc direct-current power supply 8 and the linkage mechanism 13 are respectively connected to the control assembly 10, and the control assembly 10 is used for respectively controlling the gas flow controller 6, the arc striking high-frequency power supply 7, the main arc direct-current power supply 8 and the linkage mechanism 13. The negative electrode and the positive electrode of the arc striking high-frequency power supply 7 are respectively connected with a tungsten needle 16 and a copper nozzle 17 in the plasma processing gun 1.
The ionized gas cylinder 4 and the shielding gas cylinder 5 are respectively connected with the plasma processing gun 1 and the gas shielding cover 2 through the gas flow controller 6. The positive electrode and the negative electrode of the main arc direct current power supply 8 are respectively connected with the curved surface metal part to be polished and the tungsten needle 16. The conductive work table 12 is disposed below the plasma processing gun 1, and is grounded. The linkage mechanism 13 is arranged on the conductive working platform 12, the part clamp 11 is arranged on the linkage mechanism 13, and the part clamp 11 is connected with the conductive working platform 12 and is used for clamping a metal part with a curved surface to be polished. The control assembly 10 controls the linkage mechanism 13 to move, and the linkage mechanism 13 drives the curved metal part to be polished to move through the part clamp 11, so that the pose of the curved metal part to be polished relative to the plasma processing gun 1 is changed. In this embodiment, the curved metal part to be polished may be the convex part to be polished 9, or may be the concave part to be polished 15.
The surface profile sensor 14 is used for detecting the surface profile of a set area of a curved metal part to be polished in real time, and transmitting the detected data to the control assembly 10. The control assembly 10 designs structural parameters of the pre-polished curved surface part according to structural characteristics of the curved surface metal part to be polished, and simulates a microbeam plasma polishing process by using a finite element numerical simulation analysis method, thereby determining voltage and current of a pilot arc, current of a plasma main arc, flow rates of ionized gas and shielding gas, pre-delivery time, post-delay time, muzzle height, arc movement distance and curved surface rotation speed used in the polishing process. The structural parameters include the material, shape, size, and surface roughness of the pre-polished member.
The plasma processing gun 1 includes the copper nozzle 17 and the tungsten needle 16 provided in the copper nozzle 17. In this embodiment, the tungsten needle 16 has a cylindrical shape with a diameter equal to 1.2mm and a tip end ground at 30 °; the diameter of the nozzle opening of the copper nozzle 17 is equal to 1mm; the gas shield 2 is cylindrical and has a diameter equal to 15mm.
The plasma processing gun 1 is mounted on the plasma gun fixing base 3 without movement in space. A pilot arc is generated in the plasma processing gun 1, the pilot arc high-frequency power supply 7 and the main arc direct current power supply 8 are connected in parallel to help a plasma main arc to be generated between the plasma processing gun 1 and the curved metal part to be polished, and the plasma main arc is used for polishing the surface of the curved metal part to be polished. Wherein, during plasma beam polishing, the metal surface morphology is sensitive to the magnitude of heat input, and excessive energy can cause burning loss of surface metal elements and surface morphology defects. In this embodiment, the total power of the plasma arc generating process between the plasma processing gun 1 and the surface of the curved metal part to be polished is not more than 300W.
The muzzle position of the plasma processing gun 1 is used as a reference point of the polishing path track designed by the control assembly 10, the plasma arc is influenced by gravity, an included angle between the central axis of the plasma processing gun 1 and the Z axis has an important influence on the shape of the main plasma arc, and when the central axis of the plasma processing gun 1 is coincident with the Z axis, and the plasma processing gun 1 points to the ground, the straightness of the plasma arc is best, and the input heat is uniformly distributed.
Referring to fig. 5, the linkage mechanism 13 is used for adjusting the direction and position of the curved metal part to be polished relative to the muzzle of the plasma processing gun 1, so as to control the axial distance between the muzzle of the plasma processing gun 1 and the polishing point to be unchanged, and always pass through the curved normal of the position of the polishing point. The axial distance between the position of the polishing point and the muzzle of the plasma processing gun 1 has an important influence on the distribution of the heat quantity generated by the position of the polishing point, the surface is damaged by oxidation when the distance is too low, and insufficient melting is caused when the distance is too high. In the present embodiment, the linkage mechanism 13 includes an S-axis, an L-axis, a U-axis, an R-axis, a B-axis, and a T-axis, and the S-axis, the L-axis, the U-axis, the R-axis, the B-axis, and the T-axis are connected.
The protection gas cylinder 5 and the gas protection cover 2 together form a protection component to prevent oxidation of the metal surface in the polishing process, a gas flow controller 6 is arranged between the protection gas cylinder 5 and the gas protection cover 2, the gas flow controller 6 is commanded by the control component 10 to control the pre-sending and the backward stagnation of the protection gas, and the flow rate of the protection gas is controlled in real time. The pre-feeding of the shielding gas will affect the success of the arcing, while the lag of the shielding gas can continue to prevent oxidation of the metal material surface and oxidation of the tungsten needle 16 after polishing is completed.
When the microbeam plasma polishing device polishes, the surface profile detector 14 is used for detecting the surface profile of a set area of a metal part with a curved surface to be polished in real time, transmitting detected data to the control assembly 10, further, the control assembly 10 designs structural parameters of the pre-polished part according to the structural characteristics of the metal part with the curved surface to be polished, and simulates a microbeam plasma polishing process by using a finite element numerical simulation analysis method, thereby determining various working parameters used in the polishing process. The control assembly 10 controls the linkage mechanism 13 to move according to the obtained working parameters so as to rotate the metal part with the curved surface to be polished to an initial position. Thereafter, the control assembly 10 controls the opening of the shielding gas to clean the entire gas path with the dried shielding gas; in addition, the plasma gas is started, and the control assembly 10 controls the arc striking high-frequency power supply 7 to generate a pilot arc; the arc striking high-frequency power supply 7 and the main arc direct current power supply 8 work in parallel to enable a plasma main arc to be generated between the plasma processing gun 1 and the surface of the metal workpiece to be polished, then, according to a calculation path and optimal parameters, the metal part to be polished is subjected to first-time curved surface scanning, the roughness of the irregular rough surface is greatly reduced through the first-time scanning, micro-protrusions are generated at the lap joint, and the whole polished curved surface presents parallel banded protrusion stripes; after the first scanning and polishing are finished, returning the curved surface metal part to be polished to the initial position; the control component 10 calculates the optimal polishing parameters of the covering bulge through the surface profile of the polishing area measured by the surface profile detector 14 at the moment, and then performs second-pass curved surface scanning of the covering bulge, wherein the size of the regular parallel strip-shaped strip surface formed by the first-pass scanning is reduced after the second-pass scanning; the above steps may be repeated for multiple scan passes until the desired surface roughness is achieved.
The single-pass polishing movement of the curved surface metal part to be polished relative to the muzzle of the plasma processing gun 1 is self-rotation movement of the curved surface metal part to be polished around the central axis of the plasma processing gun, the high efficiency is required for the industrialization of polishing, the time required for the polishing process is saved by adopting the spin movement energy around the central axis, and the polishing efficiency is improved. The end point of the previous single-pass scanning is finished, the main arc direct current power supply 8 is closed, the main plasma arc disappears, the starting point and the end point of the single-pass scanning are coincident due to the self-rotation motion around the central axis, the arc striking high-frequency power supply 7 keeps working until the curved surface metal part to be polished moves to the starting point of the next single-pass scanning, the main arc direct current power supply 8 is started again, and the main plasma arc is generated between the plasma processing gun 1 and the surface of the curved surface metal part to be polished again; the larger the surface roughness of the metal part with the curved surface to be polished is, the larger the total input power is, and the wider the generated molten pool width is; the size of the bulge generated at the scanning lap joint is related to the total input power, and the larger the total input power is, the larger the size of the bulge is generated; the ratio of the single-track width of the next scanning to the single-track width of the previous scanning is 1: (3-4); the total input power used in the next scanning is smaller than that used in the last scanning; the multi-channel polishing movement of the curved surface metal part to be polished relative to the muzzle of the plasma processing gun 1 is divided into multiple layers, each layer moves according to the equal arc length, namely, the current track end point is reached, after the main arc direct current power supply 8 is closed, the axial distance between the muzzle and the curved surface metal part to be polished is kept unchanged, the main arc direct current power supply 8 is started again by rotating around the central axis of the curved surface metal part to be polished to reach the starting point position of the next single polishing track until the single polishing of all layers is completed, and the multi-layer polishing procedure can ensure that the width and depth of a molten pool scanned by each single pass are consistent and the surface performance uniformity is good; the moving track of the rotary wheel preferably adopts polishing from inside to outside from the center of the curved metal part to be polished during rotary polishing, so that the generation of scale patterns on a single track due to low temperature of a substrate and large temperature gradient is avoided.
The microbeam plasma polishing device can treat regular curved surface parts and dies generated by rough machining, wherein the surface roughness Ra of the regular curved surface parts is 5-10 mu m. By using the plasma processing gun 1 with the diameter of 1mm and the plasma arc with the total power of less than 300W, the surface roughness of the metal is continuously reduced by repeatedly scanning the lap joint convex parts. The metal parts with higher original roughness require more repeated polishing than the metal parts with lower original roughness to achieve the same final target roughness. When the roughness Ra is high, a larger heat input is required to melt the high surface irregularities and other particulate matter, and the resulting puddle is also wider, allowing large area polishing to be accomplished in a shorter time and with a shorter stroke. After the first polishing, the metal surface is leveled and smooth, ra=1 μm can be achieved, but regular banded convex stripes exist, the overall surface roughness is affected, the method can be suitable for parts with low surface roughness requirements, after the second polishing is carried out to cover the convex generated by the first polishing, the height of the convex formed by the first scanning is greatly reduced, and a smoother surface can be obtained. After twice polishing processes, the surface roughness requirements of most metal parts can be met, the repeated polishing times can further reduce the surface roughness, the surface roughness Ra of the curved surface parts and the dies which are subjected to rough machining is polished between 5 and 10 mu m, the polishing roughness can reach 0.2 mu m, but when the surface roughness Ra reaches 0.2 mu m, the repeated polishing is continued to increase the surface roughness to a certain extent, and the increased surface roughness can reach 1 mu m. The reduction of the surface roughness of the curved workpiece to 0.2 μm means a 98% reduction relative to the original surface roughness Ra of the metal article of 10 um.
The invention also provides a micro-beam plasma polishing method of the curved metal part, which mainly comprises the following steps:
step one, providing the microbeam plasma polishing device for the curved metal part, placing the curved metal part to be polished on the part clamp, and polishing the curved metal part to be polished by the polishing device for the first time.
Specifically, the surface profile finder 14 measures the surface morphology of the raw material, and inputs data into the control assembly 10, the control assembly 10 designs structural parameters of the pre-polished part according to structural characteristics of the curved surface part to be polished, and simulates a microbeam plasma polishing process by using a finite element numerical simulation analysis method, thereby determining voltage and current of a pilot arc, plasma main arc current, ionized gas flow rate, muzzle height, arc movement distance and curved surface rotation speed used in the polishing process; the control assembly 10 transmits the calculated process parameters and parameters such as the flow rate of the protection gas input manually is 5L/min, the pre-delivery time is 10s, the post-lag time is 10s, and the like to the linkage mechanism 13, the main arc direct current power supply 8 and the body flow controller 6 respectively. Wherein the structural parameters include the material, shape, size, and surface roughness of the pre-polished member.
The gas flow controller 6 pre-sends dry shielding gas, nitrogen and clean gas paths, pre-sends ionized gas, high-purity argon, the arc striking high-frequency power supply 7 is started, and a pilot arc is generated in the plasma processing gun 1; and the linkage mechanism 13 moves the curved metal part to be polished according to the calculated path, and moves the selected polishing starting point to the position right below the muzzle, wherein the distance between the starting point and the muzzle is the calculated muzzle height distance. The main arc direct current power supply 8 works, and a plasma main arc is generated between the plasma processing gun 1 and the surface of the curved metal part to be polished.
According to the calculated optimal experimental parameters, the linkage mechanism 13 drives the curved metal part to be polished to move according to the calculated scanning track, as shown in fig. 6A, and the hatched area indicates the area which is not acted in the scanning. After the first polishing pass is completed, a relatively smooth surface is obtained, and as shown in fig. 6B, the main arc dc power supply 8 is stopped.
The polishing movement of the curved surface metal part to be polished relative to the muzzle of the plasma processing gun 1 is the combination of the self-rotation movement of the part to be polished around the central axis of the part to be polished and the movement of the equal arc length, when the single-pass scanning reaches the single-pass track end point, the rotation movement of the T axis (shown in figure 5) of the linkage mechanism 13 stops, the main arc direct current power supply 8 stops working, the starting point and the end point of the single-pass scanning are coincident due to the self-rotation movement around the central axis, the linkage mechanism 13 drives the equal arc length of the part to be polished to the starting point of the next single-pass scanning, the main arc direct current power supply 8 starts working again, as shown by the solid arrow in figure 6A, the main arc direct current power supply 8 moves in the arrow direction, and the dotted arrow represents the movement of the part to be polished in the arrow direction when the main arc direct current power supply 8 stops working. Finally, the curved metal part to be polished is placed on the part clamp 11 and cooled for 1min.
Step two, the surface profile detector measures the appearance of a polishing area of the metal part with the curved surface to be polished after the previous polishing, and transmits the measured data to the control component, and the control component calculates the optimal polishing parameters of the strip-shaped convex stripes generated at the scanning lap joint when the previous polishing is covered according to the structure of the metal part with the curved surface to be polished; and the polishing device polishes the curved surface metal part to be polished for the next time according to the optimal polishing parameters.
The surface profile detector 14 measures the surface morphology of the metal material polished in the previous time, and inputs the obtained data into the control assembly 10, the control assembly 10 designs the structural parameters of the pre-polished part according to the structural characteristics of the curved surface part to be polished, and simulates the microbeam plasma polishing process by using a finite element numerical simulation analysis method, thereby determining the voltage and current of the pilot arc, the plasma main arc current, the ionized gas flow rate, the muzzle height, the arc moving distance and the curved surface rotation speed used in the polishing process; the control assembly 10 transmits the calculated process parameters and parameters such as the flow rate of the shielding gas manually input at 5L/min, the pre-feeding time at 10s, the lag time at 10s, etc. to the linkage mechanism 13, the main arc direct current power supply 8 and the gas flow controller 6 respectively.
The linkage mechanism 13 moves the curved surface metal part to be polished according to the calculated path, and moves the selected polishing starting point to the position right below the muzzle, wherein the distance between the starting point and the muzzle is the calculated muzzle height distance; the main arc direct current power supply 8 works, and a plasma main arc is generated between the plasma processing gun 1 and the surface of the curved metal part to be polished; according to the calculated optimal experimental parameters, the linkage mechanism 13 drives the curved surface metal part to be polished to move according to the calculated scanning track, as shown in fig. 7A, the hatched area indicates the area which is not acted in the scanning, the relatively smooth surface is obtained after the first polishing is completed, as shown in fig. 7B, and then the main arc direct current power supply 8 stops working.
The polishing movement of the metal part with the curved surface to be polished relative to the muzzle of the plasma processing gun 1 is the combination of the self-rotation movement of the metal part with the curved surface to be polished around the central axis and the movement with equal arc length, when the single-pass scanning reaches the end point of the single-pass track, the rotation movement of the T-axis (shown in figure 5) of the linkage mechanism 13 stops, the main arc direct current power supply 8 stops working, the starting point and the end point of the single-pass scanning coincide because of the self-rotation movement around the central axis, the linkage mechanism 13 drives the movement of the metal part with equal arc length to be polished to the starting point of the next single-pass scanning, the main arc direct current power supply 8 starts working again, as shown by the solid arrow in figure 7A, the metal part with the curved surface to be polished moves in the arrow direction in the working state of the main arc direct current power supply 8, and the dotted arrow represents the metal part with the curved surface to be polished in the arrow direction in the stop working state of the main arc direct current power supply 8. Finally, the curved metal part to be polished is placed on the part clamp 11 and cooled for 1min.
And thirdly, the surface profile detector measures the surface morphology of the metal material of the metal part with the curved surface to be polished, which is obtained in the second step, and transmits the obtained data to the control component, so that the control component judges whether the surface roughness of the metal part with the curved surface to be polished meets the target requirement, if so, the polishing is finished, and otherwise, the process goes to the second step. In this embodiment, the rough-finished curved surface part and the mold having the surface roughness Ra of 5 μm to 10 μm are polished, and the roughness after polishing can be 0.2 μm.
According to the microbeam plasma polishing device and method for the curved surface metal part, disclosed by the invention, the moving track starts from the center part of the curved surface metal part to be polished during rotary polishing, and polishing is performed from inside to outside, so that the generation of scale marks on a single track due to low substrate temperature and large temperature gradient is avoided, and the polishing quality is improved. In addition, after the first polishing, the metal surface becomes smoother, but strip-shaped protruding stripes exist, the overall plane roughness is affected, then after the second polishing is carried out to cover the protrusions generated by the first polishing, the height of the protrusions formed by the first polishing is greatly reduced, so that a smoother plane can be obtained, the polishing quality and efficiency are improved, the flexibility is higher, and the polishing device is easy to use.
It will be readily appreciated by those skilled in the art that the foregoing description is merely a preferred embodiment of the invention and is not intended to limit the invention, but any modifications, equivalents, improvements or alternatives falling within the spirit and principles of the invention are intended to be included within the scope of the invention.
Claims (8)
1. A microbeam plasma polishing device for curved metal parts is characterized in that:
the polishing device comprises a control assembly, a surface profile detector, a linkage mechanism, a gas protection cover, a plasma processing gun, a plasma gun fixing base and a part clamp, wherein the surface profile detector is connected with the control assembly, the linkage mechanism is connected with the control assembly, the part clamp is arranged on the linkage mechanism, and the part clamp is used for clamping a metal part with a curved surface to be polished; the plasma processing gun is arranged on the plasma gun fixing base and is connected with the control assembly; the gas protection cover is arranged outside the plasma processing gun;
after finishing the previous polishing, the surface profile detector measures the surface morphology of the current polishing area of the metal part with the curved surface to be polished, and transmits the obtained data to the control component, so that the control component calculates and obtains the optimal polishing parameters of the strip-shaped convex stripes generated at the scanning lap joint part when the previous polishing is covered according to the surface roughness and the profile line of the metal part with the curved surface to be polished; then, the control assembly controls the linkage mechanism to drive the curved surface metal part to be polished to move relative to the plasma processing gun according to the optimal polishing parameters so as to polish the curved surface metal part to be polished for the next time, thereby covering the strip-shaped raised stripes;
the control component is used for designing structural parameters of the pre-polished curved surface metal part according to the structure of the curved surface metal part to be polished, and simulating a microbeam plasma polishing process by using a finite element numerical simulation analysis method, so as to determine working parameters in the polishing process; generating a plasma main arc between the plasma processing gun and the curved metal part to be polished; generating a pilot arc in the plasma processing gun; the working parameters comprise the voltage and the current of a pilot arc; a current of the plasma main arc; the flow rate, the pre-delivery time and the lag time of the ionized gas and the shielding gas; muzzle height of the plasma processing gun; arc moving distance and curved surface rotation speed of the curved surface metal part to be polished.
2. The microbeam plasma polishing apparatus for curved metal parts as set forth in claim 1, wherein: in the polishing process, the central axis of the plasma processing gun coincides with the normal line of the curved surface metal part to be polished at the polishing point.
3. The microbeam plasma polishing apparatus for curved metal parts as set forth in claim 1, wherein: the single-pass polishing movement of the curved surface metal part to be polished relative to the plasma processing gun is self-rotation movement of the curved surface metal part to be polished around the central axis of the curved surface metal part to be polished; and the moving track of the rotary wheel starts from the center of the curved metal part to be polished during rotary polishing, and polishing is performed from inside to outside.
4. A microbeam plasma polishing apparatus for curved metal parts as in any one of claims 1 to 3, wherein: the plasma processing gun comprises a copper nozzle and a tungsten needle arranged in the copper nozzle; the polishing device comprises an arc striking high-frequency power supply and a main arc direct current power supply which are respectively connected with the control assembly, and the anode and the cathode of the main arc direct current power supply are respectively connected with the curved surface metal part to be polished and the tungsten needle; and the negative electrode and the positive electrode of the arc striking high-frequency power supply are respectively connected with the tungsten needle and the copper nozzle.
5. A microbeam plasma polishing apparatus for curved metal parts as in any one of claims 1 to 3, wherein: the polishing device further comprises an ionized gas cylinder, a protective gas cylinder and a flow controller, wherein the flow controller is connected to the control assembly, and the ionized gas cylinder and the protective gas cylinder are respectively connected with the plasma processing gun and the gas protection cover through the flow controller.
6. A microbeam plasma polishing apparatus for curved metal parts as in any one of claims 1 to 3, wherein: the total input power used in the next scanning is smaller than that used in the last scanning, and the ratio of the single-channel width of the next scanning to the single-channel width of the last scanning is 1 (3-4).
7. A microbeam plasma polishing method for curved metal parts, which is characterized by comprising the following steps:
(1) Providing a microbeam plasma polishing device for curved metal parts according to any one of claims 1 to 6, and placing the curved metal parts to be polished on the part fixture, wherein the polishing device polishes the curved metal parts to be polished for the first time;
(2) The surface profile detector measures the appearance of a polishing area of the metal part with the curved surface to be polished after the previous polishing, and transmits the measured data to the control component, and the control component calculates the optimal polishing parameters of the strip-shaped raised stripes generated at the scanning lap joint part during the covering of the previous polishing according to the structure of the metal part with the curved surface to be polished; the polishing device polishes the curved surface metal part to be polished for the next time according to the optimal polishing parameters;
(3) And (3) the surface profile detector measures the surface morphology of the metal material of the metal part with the curved surface to be polished, which is obtained in the step (2), and transmits the obtained data to the control component, so that the control component judges whether the surface roughness of the metal part with the curved surface to be polished meets the target requirement, if so, the polishing is finished, and otherwise, the step (2) is carried out.
8. The microbeam plasma polishing method of a curved metal part as recited in claim 7, wherein: the flow rate of the shielding gas entering the gas shielding cover is 5L/min, the pre-feeding time is 10s, and the hysteresis time is 10s.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811407444.1A CN109434570B (en) | 2018-11-23 | 2018-11-23 | Microbeam plasma polishing device and method for curved metal parts |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811407444.1A CN109434570B (en) | 2018-11-23 | 2018-11-23 | Microbeam plasma polishing device and method for curved metal parts |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109434570A CN109434570A (en) | 2019-03-08 |
| CN109434570B true CN109434570B (en) | 2023-09-01 |
Family
ID=65554755
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811407444.1A Active CN109434570B (en) | 2018-11-23 | 2018-11-23 | Microbeam plasma polishing device and method for curved metal parts |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109434570B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI738427B (en) * | 2020-07-21 | 2021-09-01 | 財團法人金屬工業研究發展中心 | Apparatus capable of local polishing and plasma-electrolytic polishing system |
| CN113477944A (en) * | 2021-06-22 | 2021-10-08 | 南京联空智能增材研究院有限公司 | Surface treatment method for additive product |
| CN113547389B (en) * | 2021-07-28 | 2022-07-05 | 大连理工大学 | Ultra-precise grinding process for tungsten alloy part with complex curved surface |
| CN114473815B (en) * | 2022-02-18 | 2023-04-14 | 南通元兴智能科技有限公司 | A single face burnishing machine for carborundum processing |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2003026846A1 (en) * | 2001-09-13 | 2003-04-03 | Nederlandse Organisatie Voor Toegepast- Natuurwetenschappelijk Onderzoek Tno | Method and apparatus for polishing a workpiece surface |
| CN104526470A (en) * | 2015-01-04 | 2015-04-22 | 中国科学院光电技术研究所 | Ion beam smoothing method for curved surface optical element |
| CN106392821A (en) * | 2016-11-04 | 2017-02-15 | 中国航空工业集团公司北京航空精密机械研究所 | Free curved prism machining method |
| CN108311960A (en) * | 2018-03-21 | 2018-07-24 | 大连理工大学 | A kind of burnishing device and method of freeform optics surface |
| CN108326432A (en) * | 2018-03-08 | 2018-07-27 | 北京工业大学 | A kind of laser polishing device and method of SLM moldings TC4 alloys |
-
2018
- 2018-11-23 CN CN201811407444.1A patent/CN109434570B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2003026846A1 (en) * | 2001-09-13 | 2003-04-03 | Nederlandse Organisatie Voor Toegepast- Natuurwetenschappelijk Onderzoek Tno | Method and apparatus for polishing a workpiece surface |
| CN104526470A (en) * | 2015-01-04 | 2015-04-22 | 中国科学院光电技术研究所 | Ion beam smoothing method for curved surface optical element |
| CN106392821A (en) * | 2016-11-04 | 2017-02-15 | 中国航空工业集团公司北京航空精密机械研究所 | Free curved prism machining method |
| CN108326432A (en) * | 2018-03-08 | 2018-07-27 | 北京工业大学 | A kind of laser polishing device and method of SLM moldings TC4 alloys |
| CN108311960A (en) * | 2018-03-21 | 2018-07-24 | 大连理工大学 | A kind of burnishing device and method of freeform optics surface |
Non-Patent Citations (1)
| Title |
|---|
| 大尺寸自由曲面铝反射镜超精密抛光工艺;潘龙;宫虎;房丰洲;;纳米技术与精密工程(02);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109434570A (en) | 2019-03-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109434570B (en) | Microbeam plasma polishing device and method for curved metal parts | |
| US20220266370A1 (en) | Method and apparatus for fabrication of articles by molten and semi-molten deposition | |
| CN106735967B (en) | A kind of method of ultrasonic vibration assistant electric arc increasing material manufacturing control shape control | |
| WO2020037804A1 (en) | Intelligent additive method for magnetic field-controlled arc robot | |
| CN109226755B (en) | Additive manufacturing device and method for improving bonding strength between deposition layers of additive component | |
| WO2018196106A1 (en) | Combining device for laser heating power layer-by-layer interaction additive manufacturing | |
| CN108723549A (en) | A kind of electric arc increasing material manufacturing method | |
| CN100526512C (en) | Steam turbine valve manifold stellite alloy plasma spray welding method and equipment | |
| CN109623098A (en) | A kind of compound increasing material method of MIG-TIG | |
| Zahedi et al. | Picosecond laser treatment of metal-bonded CBN and diamond superabrasive surfaces | |
| CN110744303B (en) | Electric arc additive and forging-milling combined machining forming device and method | |
| CN107096972B (en) | A kind of method of laser soldering mono-layer diamond tool | |
| TWI572733B (en) | Partial spray refurbishment of sputtering targets | |
| CN108672849B (en) | Micro-beam arc selective fusion and electric spark layered milling composite additive manufacturing method | |
| CN107937910B (en) | Defect detection device and detection and repair method in laser metal cladding rapid forming process | |
| CN111283305A (en) | Liquid nitrogen follow-up cooling additive manufacturing device and method | |
| CN109048054B (en) | Multi-axis laser-abrasive water jet precise polishing synchronous processing method | |
| CN107520444A (en) | Deposition apparatus and deposition method | |
| CN110732775A (en) | double-electric-arc auxiliary laser welding device and method | |
| US6297466B1 (en) | Method for repairing steel spray-formed tooling with TIG welding process | |
| CN109366255A (en) | A kind of the microplasma burnishing device and method of metal surface | |
| CN116000457B (en) | Laser coaxial-induction multi-TIG electric arc multi-wire rapid additive manufacturing method and manufacturing system | |
| CN104046983A (en) | Titanium alloy thin-wall blade laser-cladding low-stress local orientation cooling restoration method | |
| CN104775120A (en) | Multifunctional electric discharge machine | |
| CN114130581A (en) | Laser cold spraying assembly and spraying system |
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 |