Friction heat micro-fusion penetration modified polishing method

Abstract

A friction heat micro-fusion penetration modified polishing method is characterized by comprising the following steps that (1) firstly, a penetration modified reinforced phase is added into a polishing solution, the penetration modified reinforced phase is gallium or gallium-indium, gallium-tin or gallium-indium-tin gallium-containing series alloy with the melting point being 20-300 DEG C, the penetration modified reinforced phase is evenly dispersed in the polishing solution, and the particle size ranges from 100 nm to 20 microns; during grinding or polishing, the hard abrasive particles and a workpiece are subjected to micro-cutting action to generate friction heat, and the heat is transferred to the low-melting-point gallium alloy to enable the low-melting-point gallium alloy to be subjected to micro-melting on a friction interface; (2) the gallium alloy in the polishing solution is slightly molten and then locally infiltrates the surface of the aluminum-containing workpiece, metal gallium in the molten low-melting-point alloy permeates into an aluminum grain boundary and diffuses along the grain boundary, intergranular cracks are generated on a material of a friction interface and are modified, and a modified layer which is relatively easy to remove is generated on the outermost layer of the workpiece; and (3) the cutting effect of the hard abrasive particles and the penetration modification effect of the molten alloy are synergistically and alternately carried out, and the workpiece is ground and polished with high quality and high efficiency. The machining efficiency is high, and the precision is good.

Description

Technical Field

[0001] This invention relates to a polishing technology, particularly a surface polishing technology for aluminum alloy parts, specifically a frictional heat micro-melting penetration modification polishing method that achieves high-quality polishing by adding a penetration modification reinforcing phase. Background Technology

[0002] As is well known, grinding and polishing are key processes for achieving high precision and low surface roughness. When grinding or polishing slurries are introduced to grind and polish workpieces, fine abrasive grains perform micro-cutting. However, a large number of abrasive grains are in a non-active cutting state, or merely engage in pointless rolling and friction on the workpiece surface, failing to effectively participate in material removal. This results in low efficiency for traditional grinding and polishing processes. Furthermore, the uneven distribution of abrasive grains within the processing area makes them prone to accumulation or loss due to centrifugal force or fluid action, leading to inconsistent material removal rates in different areas of the workpiece. This not only reduces overall efficiency but also makes subsequent surface accuracy control difficult. Therefore, improving grinding and polishing efficiency has become a key focus in the industry.

[0003] Gallium is a low-melting-point metal with a melting point of only 29.8°C. Gallium can spontaneously form low-melting-point alloys with metals such as indium and tin, and the melting point of the alloy can be adjusted according to the metal content. At room temperature, gallium metal can wet the surface of aluminum and aluminum-containing alloys and oxides, penetrating into the interstitial spaces of the workpiece's crystal lattice, thereby modifying the workpiece surface and improving its machinability.

[0004] Polishing slurry is a key element in the grinding and polishing process, and its performance directly affects the grinding and polishing effect and processing efficiency of the workpiece. To address the issue of low grinding and polishing efficiency, a friction-heat micro-melting and penetrating modified polishing slurry reinforcing phase is added to the polishing slurry. Using a corresponding polishing method, the alternating action of the penetrating modification of the reinforcing phase and the micro-cutting action of the abrasive grains during the grinding and polishing process achieves high-quality grinding and polishing of aluminum and aluminum alloys and oxides, thereby improving grinding and polishing efficiency. Summary of the Invention

[0005] The purpose of this invention is to address the problems of low processing efficiency and difficulty in meeting design requirements in existing polishing methods using polishing slurries. The invention proposes a frictional heat micro-melting penetration modification polishing method that achieves high-efficiency and high-quality grinding and polishing by adding a penetration-modifying reinforcing phase to the polishing slurry.

[0006] The technical solution of this invention is: A method for frictional thermal micro-melting penetration modification and polishing, characterized by comprising the following steps: (1) First, a penetration-modified reinforcing phase is added to the polishing slurry. The penetration-modified reinforcing phase is gallium or gallium-indium, gallium-tin, gallium-indium-tin alloys with a melting point of 20℃~300℃. It is uniformly dispersed in the polishing slurry with a particle size between 100nm and 20μm. During grinding or polishing, the hard abrasive grains generate frictional heat through micro-cutting action with the workpiece. The heat is transferred to the low-melting-point gallium alloy, causing it to undergo micro-melting at the friction interface. (2) After the gallium alloy in the polishing solution is slightly melted, it partially wets the surface of the aluminum-containing workpiece. The metallic gallium in the melted low-melting-point alloy penetrates into the aluminum grain boundary and diffuses along the grain boundary. The material at the friction interface is modified by intergranular cracks. A relatively easy-to-remove modified layer is generated on the outermost layer of the workpiece. (3) The workpiece is ground and polished with high quality and high efficiency by the synergistic alternation of the cutting action of hard abrasive grains and the infiltration modification action of molten alloy.

[0007] The polishing conditions of this invention are a polishing pressure of 5-10 psi, a rotation speed of 40-90 rpm, and a polishing fluid supply flow rate of 20-50 mL / min.

[0008] The morphology of the permeation-modified enhanced phase dispersion particles is a core-shell structure. They exist in the polishing solution in the form of a polymer coating on the gallium alloy particles to prevent gallium alloy oxidation. The preparation method is to use a polymer surfactant as the coating material, heat and melt the gallium alloy in water, ultrasonically disperse it, and then cool it to solidify the gallium alloy.

[0009] The amount of the permeation-modified reinforcing phase added is 0.4-1% of the weight of water in the polishing solution, and the weight ratio of the phase to the hard abrasive particles is 1:3-10.

[0010] The grinding and polishing method of the present invention can be used for grinding and polishing of metals, alloys and metal compounds that are easily etched by gallium, such as aluminum, aluminum alloys and sapphire.

[0011] The abrasive grains are hard abrasive grains. These hard abrasive grains are diamond, cubic boron nitride, or silicon carbide abrasives, with a particle size between 10 nm and 50 μm.

[0012] The working principle of this invention is: When hard abrasive grains in the polishing slurry come into contact with the workpiece, friction and micro-cutting occur, generating frictional heat. This heat is transferred through the polishing slurry to the penetrating modified reinforcing phase, which then begins to melt under heat.

[0013] After the infiltration-modified reinforcing phase melts upon heating, it wets the surface of the workpiece, penetrates the grain boundaries of the workpiece surface material and diffuses, thereby modifying the workpiece surface, reducing its hardness and improving its machinability.

[0014] The micro-cutting action of abrasive particles and the penetrating modification effect of reinforcing phases occur alternately, resulting in high-quality surfaces that are obtained efficiently on the workpiece.

[0015] The beneficial effects of this invention are: This invention uses hard abrasive grains such as diamond as abrasives and low-melting-point alloys such as gallium indium as polishing fluid to penetrate and modify the reinforcing phase. The cutting action of the abrasive grains generates heat to melt the reinforcing phase and penetrate and modify the workpiece. The cutting and penetration modification work together on aluminum, aluminum alloys and sapphire to achieve high-quality and high-efficiency grinding and polishing.

[0016] Under the same conditions, the polishing roughness of the present invention can be improved by 2-3 grades, and the efficiency can be improved by more than 30%. Attached Figure Description

[0017] Figure 1 These are metallographic images of the edge and center polishing effects in the comparative polishing slurry of this invention without the addition of gallium alloy penetration modification reinforcing phase. Among them, (a) is the edge metallographic image, and (b) is the center metallographic image.

[0018] Figure 2 Metallographic images showing the edge and center polishing effects after adding a gallium alloy infiltration modification reinforcing phase to the polishing slurry in Embodiment 1 of the present invention. Detailed Implementation

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0020] The structures, proportions, and sizes illustrated in the accompanying drawings are merely for illustrative purposes and to aid those skilled in the art in understanding and reading the invention. They are not intended to limit the scope of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of the invention, should still fall within the scope of the technical content disclosed herein. Furthermore, terms such as "upper," "lower," "left," "right," and "middle" used in this specification are merely for clarity and not intended to limit the scope of implementation. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention's implementation.

[0021] Example 1.

[0022] A permeation-modified polishing slurry was prepared with a weight ratio of liquid gallium, polyvinylpyrrolidone K30, and water of 2:1:500. The slurry was ultrasonicated in a 40°C water bath for 1 hour, and the particle size of the liquid gallium was between 100nm and 20μm.

[0023] A polishing slurry containing a penetration-modified reinforcing phase was prepared: the abrasive was W3.5 single-crystal diamond micro powder, with a weight ratio of 10:1 to gallium, and pH agents, complexing agents, etc. were added in proportion.

[0024] Polishing process parameters: polishing pressure 10psi, rotation speed 90rpm, polishing fluid supply flow rate 20mL / min.

[0025] Polishing single-crystal sapphire material with this polishing slurry containing the penetrating modified reinforcing phase and the corresponding polishing method results in a surface roughness below 10 nm. For example... Figure 2 As shown.

[0026] Example 2.

[0027] A permeation-modified polishing slurry was prepared with a reinforcing phase consisting of gallium-indium alloy, sodium dodecylbenzenesulfonate, and water in a weight ratio of 5:1:400, and ultrasonicated in an 80°C water bath for 1 hour. The particle size of the gallium-indium alloy was between 100 nm and 20 μm.

[0028] A polishing slurry containing a penetrating modified reinforcing phase is prepared: the abrasive is silicon carbide, and the weight ratio of silicon carbide to gallium indium alloy is 5:1. pH agent, complexing agent, etc. are added in proportion.

[0029] Polishing process parameters: polishing pressure 5psi, rotation speed 60rpm, polishing fluid supply flow rate 50mL / min.

[0030] When aluminum materials are polished using the polishing slurry containing the penetrating modified reinforcing phase and the corresponding polishing method, the surface roughness is below 5 nm.

[0031] Example 3.

[0032] A permeation-modified polishing slurry was prepared with a reinforcing phase consisting of gallium indium tin alloy, polyethylene glycol, and water in a weight ratio of 5:2:500, and ultrasonicated in a 100°C water bath for 1 hour. The particle size of the gallium indium tin alloy was between 100 nm and 20 μm.

[0033] A polishing slurry containing a penetration-modified reinforcing phase was prepared: the abrasive was cubic boron nitride, with a weight ratio of 3:1 to gallium indium alloy, and pH agents, complexing agents, etc. were added in proportion.

[0034] When aluminum alloy materials are polished using the polishing slurry containing the penetrating modified reinforcing phase and the corresponding polishing method, the surface roughness is below 10 nm.

[0035] Comparative example.

[0036] Polishing conditions were: rotation speed 80 rpm (upper) and 85 rpm (lower); polishing pressure 200 kPa; polishing fluid flow rate 20; and polishing time 60 min.

[0037] Polishing fluid ratio (1) Gallium-free: Diamond 4wt%, the remainder is water; polishing effect is as follows Figure 1 As shown.

[0038] from Figure 1 , 2It is evident that there is little change between the two, but the edge (surface) roughness increases significantly by 50%.

[0039] The above embodiments are merely preferred embodiments of the present invention. It should be noted that those skilled in the art can make several improvements and equivalent substitutions without departing from the principle of the present invention. All such improvements and equivalent substitutions to the claims of the present invention fall within the protection scope of the present invention.

[0040] All parts not covered in this invention are the same as or can be implemented using existing technologies.

Claims

1. A method for frictional thermal micro-melting penetration modification and polishing, characterized in that: Includes the following steps: (1) First, a penetration-modified reinforcing phase is added to the polishing slurry. The penetration-modified reinforcing phase is gallium or gallium-indium, gallium-tin, gallium-indium-tin alloys containing gallium, which are uniformly dispersed in the polishing slurry with a particle size between 100 nm and 20 μm. During grinding or polishing, the hard abrasive grains generate frictional heat through micro-cutting action with the workpiece. The heat is transferred to the low-melting-point gallium alloy, causing it to melt slightly at the friction interface. (2) After the gallium alloy in the polishing solution is slightly melted, it partially wets the surface of the aluminum-containing workpiece. The metallic gallium in the melted low-melting-point alloy penetrates into the aluminum grain boundary and diffuses along the grain boundary. The material at the friction interface is modified by intergranular cracks. A relatively easy-to-remove modified layer is generated on the outermost layer of the workpiece. (3) The workpiece is ground and polished with high quality and high efficiency by the synergistic alternation of the cutting action of hard abrasive grains and the infiltration modification action of molten alloy.

2. The method according to claim 1, characterized in that, The polishing conditions are: polishing pressure 5-10 psi, rotation speed 40-90 rpm, and polishing fluid supply flow rate 20-50 mL / min.

3. The method according to claim 1, characterized in that, The morphology of the permeation-modified enhanced phase dispersion particles is a core-shell structure. They exist in the polishing solution in the form of a polymer coating on the gallium alloy particles to prevent gallium alloy oxidation. The preparation method is to use a polymer surfactant as the coating material, heat and melt the gallium alloy in water, ultrasonically disperse it, and then cool it to solidify the gallium alloy.

4. The method according to claim 1, characterized in that, The amount of the permeation-modified reinforcing phase added is 0.4-1% of the weight of water in the polishing solution.

5. The method according to claim 1, characterized in that, This grinding and polishing method can be used for grinding and polishing metals, alloys, and metal compounds that are easily etched by gallium, such as aluminum, aluminum alloys, and sapphire.

6. The method according to claim 1, characterized in that, The abrasive grains mentioned are hard abrasive grains.

7. The method according to claim 6, characterized in that, The hard abrasive particles are diamond, cubic boron nitride, and silicon carbide abrasives, with a particle size between 10 nm and 50 μm.

Images