Die-casting release agent special for magnesium alloy automobile structural part

Abstract

The invention discloses a die-casting release agent special for a magnesium alloy automobile structural part. The die-casting release agent comprises the following raw materials in parts by weight: 35-40 parts of silicone oil, 15-20 parts of modified volcanic ash, 3-5 parts of a silane coupling agent, 3-5 parts of fatty alcohol-polyoxyethylene ether, 2-4 parts of an antioxidant and 20-30 parts of deionized water. The silicone oil serves as a basic film forming substance, a uniform lubricating film is formed on the surface of a mold, the adhesive force of molten magnesium alloy and a mold cavity is directly reduced, and demolding resistance is reduced; the porous structure of the modified volcanic ash can adsorb and uniformly bear lubricating components such as silicone oil, and local loss of the lubricating film is avoided.

Description

Technical Field

[0001] This invention relates to the field of mold release agent technology, specifically to a special die-casting mold release agent for magnesium alloy automotive structural parts. Background Technology

[0002] With the advancement of automotive lightweighting trends, magnesium alloys, due to their advantages such as low density, high specific strength, and good vibration damping performance, are increasingly widely used in automotive structural components, such as engine mounts, chassis components, and transmission housings. Die casting is the main forming method for magnesium alloy automotive structural components. Its core process involves rapidly filling molten magnesium alloy into a mold cavity under high pressure, and then smoothly demolding it after cooling and solidification. Therefore, the performance of the release agent directly affects the casting quality, production efficiency, and mold life. Existing die casting release agents tend to affect the surface quality of castings and have weak demolding effects, affecting demolding efficiency. Based on this, this invention further improves upon them. Summary of the Invention

[0003] In view of the deficiencies of the prior art, the purpose of this invention is to provide a special die-casting release agent for magnesium alloy automotive structural parts, so as to solve the problems mentioned in the background art.

[0004] The present invention solves the technical problem by adopting the following technical solution: This invention provides a special die-casting release agent for magnesium alloy automotive structural parts. The die-casting release agent comprises the following raw materials in parts by weight: 35-40 parts silicone oil, 15-20 parts modified volcanic ash, 3-5 parts silane coupling agent, 3-5 parts fatty alcohol polyoxyethylene ether, 2-4 parts antioxidant, and 20-30 parts deionized water.

[0005] Preferably, the silane coupling agent is silane coupling agent KH560; the antioxidant is antioxidant 1010.

[0006] Preferably, the modified pozzolanic material is prepared by: S01: Preheat the volcanic ash at 55-60℃ for 1 hour, and then ball mill the preheated volcanic ash and sodium alginate agent at a weight ratio of (7-11):5 for one stage. After ball milling, a volcanic ash-sodium alginate combined solution is obtained. S02: Volcanic ash-sodium alginate combined liquid and modified additives are ball-milled at a weight ratio of (8-12):5 for secondary treatment. After ball milling, the mixture is filtered and dried to obtain modified volcanic ash.

[0007] Preferably, the ball milling speed for the first stage of ball milling is 1000-1500 r / min, and the milling time is 2 h; the ball milling speed for the second stage of ball milling is 750-850 r / min, and the milling time is 1 h.

[0008] Preferably, the sodium alginate agent is prepared by: S01a: Add 3-5 parts of sodium lignosulfonate solution and 2-4 parts of sodium alginate powder to 5-8 parts of barium nitrate solution and stir thoroughly to obtain sodium alginate solution; S02b: Mix 4-7 parts of silica, 1-3 parts of nano-silica sol, 2-3 parts of sodium silicate solution with a mass fraction of 8% and 7-11 parts of kaolin to obtain kaolin liquid. Sodium alginate solution and kaolin solution were mixed at a weight ratio of 5:3 and ball-milled at a speed of 1050-1100 r / min for 2 hours. After ball milling, the mixture was filtered and dried to obtain sodium alginate solution.

[0009] Preferably, the sodium lignosulfonate solution has a mass fraction of 10-15%; and the barium nitrate solution has a mass fraction of 2-5%.

[0010] Preferably, the modified additive is prepared by: sintering sheet graphene, carbon nanotubes and lanthanum oxide together, and after sintering, the modified additive is obtained.

[0011] Preferably, the sintering temperature of the blending sintering treatment is 350-400℃, and the sintering time is 1 hour.

[0012] Preferably, the mass ratio of the sheet graphene, carbon nanotubes and lanthanum oxide is (4-6):3:(1-2).

[0013] Compared with the prior art, the present invention has the following beneficial effects: In this invention, silicone oil serves as the base film-forming substance, forming a uniform lubricating film on the mold surface. This directly reduces the adhesion between the molten magnesium alloy and the mold cavity, decreasing demolding resistance. The porous structure of the modified volcanic ash adsorbs and uniformly carries lubricating components such as silicone oil, preventing localized deficiencies in the lubricating film. Furthermore, the lubricating groups introduced after modification (from sodium alginate) synergistically enhance demolding smoothness with the silicone oil, reducing the risk of casting jamming and deformation, and increasing the success rate of single-shot demolding. The silane coupling agent (KH560) improves the compatibility between the organic components (silicone oil) and the inorganic components (modified volcanic ash), preventing precipitation or agglomeration of the release agent due to uneven component dispersion, thus reducing surface pitting and flow marks on the casting. Defects such as these are eliminated; after two-stage ball milling, the modified volcanic ash has a fine particle size and uniform distribution. When mixed with other raw materials, the resulting release film has high density, which can not only isolate the mold from the direct impact of high-temperature molten metal, but also prevent the release agent residue from adhering to the casting surface, thus improving the surface finish of the casting; the antioxidant (1010) can inhibit the oxidative degradation of organic components such as silicone oil in the high-temperature environment of magnesium alloy die casting, preventing the release agent from stratification and failure due to long-term use, and extending its storage and use cycle; the combination of sodium alginate and kaolin (sodium alginate preparation steps) improves the dispersion stability of the modified volcanic ash, reduces the precipitation and stratification of the release agent during storage or use, and ensures that the release agent composition is uniform and consistent with each spray.

[0014] The sheet-like graphene and carbon nanotubes in the modified additives have excellent wear resistance and thermal conductivity. They can be uniformly dispersed in the release film through modified volcanic ash, which can improve the high-temperature wear resistance of the release film and reduce the scratching of the mold surface when the casting is removed. Lanthanum oxide can form a slight passivation protective layer with the mold surface at high temperature, and at the same time form stable compounds with impurity elements (such as aluminum and zinc) in magnesium alloy, so as to avoid the corrosion of the mold surface by high-temperature molten metal and delay the aging of the mold. Detailed Implementation

[0015] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to specific examples. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] This embodiment provides a special die-casting release agent for magnesium alloy automotive structural parts. The die-casting release agent comprises the following raw materials in parts by weight: 35-40 parts silicone oil, 15-20 parts modified volcanic ash, 3-5 parts silane coupling agent, 3-5 parts fatty alcohol polyoxyethylene ether, 2-4 parts antioxidant, and 20-30 parts deionized water.

[0017] In this embodiment, the silane coupling agent is silane coupling agent KH560; the antioxidant is antioxidant 1010.

[0018] The method for preparing the modified pozzolanic in this embodiment is as follows: S01: Preheat the volcanic ash at 55-60℃ for 1 hour, and then ball mill the preheated volcanic ash and sodium alginate agent at a weight ratio of (7-11):5 for one stage. After ball milling, a volcanic ash-sodium alginate combined solution is obtained. S02: Volcanic ash-sodium alginate combined liquid and modified additives are ball-milled at a weight ratio of (8-12):5 for secondary treatment. After ball milling, the mixture is filtered and dried to obtain modified volcanic ash.

[0019] Preferably, the ball milling speed for the first stage of ball milling is 1000-1500 r / min, and the milling time is 2 h; the ball milling speed for the second stage of ball milling is 750-850 r / min, and the milling time is 1 h.

[0020] The preparation method of sodium alginate in this embodiment is as follows: S01a: Add 3-5 parts of sodium lignosulfonate solution and 2-4 parts of sodium alginate powder to 5-8 parts of barium nitrate solution and stir thoroughly to obtain sodium alginate solution; S02b: Mix 4-7 parts of silica, 1-3 parts of nano-silica sol, 2-3 parts of sodium silicate solution with a mass fraction of 8% and 7-11 parts of kaolin to obtain kaolin liquid. Sodium alginate solution and kaolin solution were mixed at a weight ratio of 5:3 and ball-milled at a speed of 1050-1100 r / min for 2 hours. After ball milling, the mixture was filtered and dried to obtain sodium alginate solution.

[0021] In this embodiment, the sodium lignosulfonate solution has a mass fraction of 10-15%; the barium nitrate solution has a mass fraction of 2-5%.

[0022] The modified additive in this embodiment is prepared by: sintering sheet graphene, carbon nanotubes and lanthanum oxide together, and obtaining the modified additive after sintering.

[0023] In this embodiment, the sintering temperature for the blending sintering treatment is 350-400℃, and the sintering time is 1 hour.

[0024] In this embodiment, the mass ratio of sheet graphene, carbon nanotubes and lanthanum oxide is (4-6):3:(1-2).

[0025] Example 1. This embodiment provides a special die-casting release agent for magnesium alloy automotive structural parts. The die-casting release agent comprises the following raw materials in parts by weight: 35 parts silicone oil, 15 parts modified volcanic ash, 3 parts silane coupling agent, 3 parts fatty alcohol polyoxyethylene ether, 2 parts antioxidant, and 20 parts deionized water.

[0026] In this embodiment, the silane coupling agent is silane coupling agent KH560; the antioxidant is antioxidant 1010.

[0027] The method for preparing the modified pozzolanic in this embodiment is as follows: S01: Preheat the volcanic ash at 55℃ for 1 hour, then ball mill the preheated volcanic ash and sodium alginate at a weight ratio of 7:5 for primary treatment. After ball milling, a combined volcanic ash-sodium alginate solution is obtained. S02: Volcanic ash-sodium alginate combined liquid and modified additives are further ball-milled at a weight ratio of 8:5. After ball milling, the mixture is filtered and dried to obtain modified volcanic ash.

[0028] Preferably, the ball milling speed for the first stage of ball milling is 1000 r / min, and the milling time is 2 h; the ball milling speed for the second stage of ball milling is 750 r / min, and the milling time is 1 h.

[0029] The preparation method of sodium alginate in this embodiment is as follows: S01a: Add 3 parts sodium lignosulfonate solution and 2 parts sodium alginate powder to 5 parts barium nitrate solution and stir thoroughly to obtain sodium alginate solution; S02b: Mix 4 parts of silica, 1 part of nano silica sol, 2 parts of sodium silicate solution with a mass fraction of 8% and 7 parts of kaolin to obtain kaolin liquid. Sodium alginate solution and kaolin solution were mixed at a weight ratio of 5:3 and ball-milled at a speed of 1050 r / min for 2 hours. After ball milling, the mixture was filtered and dried to obtain sodium alginate solution.

[0030] In this embodiment, the sodium lignosulfonate solution has a mass fraction of 10%; the barium nitrate solution has a mass fraction of 2%.

[0031] The modified additive in this embodiment is prepared by: sintering sheet graphene, carbon nanotubes and lanthanum oxide together, and obtaining the modified additive after sintering.

[0032] In this embodiment, the sintering temperature for the blending sintering process is 350°C, and the sintering time is 1 hour.

[0033] In this embodiment, the mass ratio of sheet graphene, carbon nanotubes, and lanthanum oxide is 4:3:1.

[0034] Example 2. This embodiment provides a special die-casting release agent for magnesium alloy automotive structural parts. The die-casting release agent comprises the following raw materials in parts by weight: 40 parts silicone oil, 20 parts modified volcanic ash, 5 parts silane coupling agent, 5 parts fatty alcohol polyoxyethylene ether, 4 parts antioxidant, and 30 parts deionized water.

[0035] In this embodiment, the silane coupling agent is silane coupling agent KH560; the antioxidant is antioxidant 1010.

[0036] The method for preparing the modified pozzolanic in this embodiment is as follows: S01: Preheat the volcanic ash at 60℃ for 1 hour, and then ball mill the preheated volcanic ash and sodium alginate at a weight ratio of 11:5 for one stage. After ball milling, a combined volcanic ash-sodium alginate solution is obtained. S02: Volcanic ash-sodium alginate combined liquid and modified additives are further ball-milled at a weight ratio of 12:5. After ball milling, the mixture is filtered and dried to obtain modified volcanic ash.

[0037] Preferably, the ball milling speed for the first stage of ball milling is 1500 r / min, and the ball milling time is 2 h; the ball milling speed for the second stage of ball milling is 850 r / min, and the ball milling time is 1 h.

[0038] The preparation method of sodium alginate in this embodiment is as follows: S01a: Add 5 parts of sodium lignosulfonate solution and 4 parts of sodium alginate powder to 8 parts of barium nitrate solution and stir thoroughly to obtain sodium alginate solution; S02b: Mix 7 parts of silica, 3 parts of nano silica sol, 3 parts of sodium silicate solution with a mass fraction of 8% and 11 parts of kaolin to obtain kaolin liquid. Sodium alginate solution and kaolin solution were mixed at a weight ratio of 5:3 and ball-milled at a speed of 1100 r / min for 2 hours. After ball milling, the mixture was filtered and dried to obtain sodium alginate solution.

[0039] In this embodiment, the sodium lignosulfonate solution has a mass fraction of 15%; the barium nitrate solution has a mass fraction of 5%.

[0040] The modified additive in this embodiment is prepared by: sintering sheet graphene, carbon nanotubes and lanthanum oxide together, and obtaining the modified additive after sintering.

[0041] In this embodiment, the sintering temperature for the blending sintering process is 400℃, and the sintering time is 1 hour.

[0042] In this embodiment, the mass ratio of sheet graphene, carbon nanotubes, and lanthanum oxide is 6:3:2.

[0043] Example 3. This embodiment provides a special die-casting release agent for magnesium alloy automotive structural parts. The die-casting release agent comprises the following raw materials in parts by weight: 37.5 parts silicone oil, 17.5 parts modified volcanic ash, 4 parts silane coupling agent, 4 parts fatty alcohol polyoxyethylene ether, 3 parts antioxidant, and 25 parts deionized water.

[0044] In this embodiment, the silane coupling agent is silane coupling agent KH560; the antioxidant is antioxidant 1010.

[0045] The method for preparing the modified pozzolanic in this embodiment is as follows: S01: Preheat the volcanic ash at 57℃ for 1 hour, then ball mill the preheated volcanic ash and sodium alginate at a weight ratio of 9:5 for primary treatment. After ball milling, a combined volcanic ash-sodium alginate solution is obtained. S02: Volcanic ash-sodium alginate combined liquid and modified additives are further ball-milled at a weight ratio of 10:5. After ball milling, the mixture is filtered and dried to obtain modified volcanic ash.

[0046] Preferably, the ball milling speed for the first stage of ball milling is 1250 r / min, and the ball milling time is 2 h; the ball milling speed for the second stage of ball milling is 800 r / min, and the ball milling time is 1 h.

[0047] The preparation method of sodium alginate in this embodiment is as follows: S01a: Add 4 parts of sodium lignosulfonate solution and 3 parts of sodium alginate powder to 6.5 parts of barium nitrate solution and stir thoroughly to obtain sodium alginate solution; S02b: 5.5 parts of silica, 2 parts of nano silica sol, 2.5 parts of sodium silicate solution with a mass fraction of 8% and 9 parts of kaolin are mixed and stirred thoroughly to obtain kaolin liquid; Sodium alginate solution and kaolin solution were mixed at a weight ratio of 5:3 and ball-milled at a speed of 1070 r / min for 2 hours. After ball milling, the mixture was filtered and dried to obtain sodium alginate solution.

[0048] In this embodiment, the sodium lignosulfonate solution has a mass fraction of 12.5%; the barium nitrate solution has a mass fraction of 3.5%.

[0049] The modified additive in this embodiment is prepared by: sintering sheet graphene, carbon nanotubes and lanthanum oxide together, and obtaining the modified additive after sintering.

[0050] In this embodiment, the sintering temperature for the blending sintering process is 375°C, and the sintering time is 1 hour.

[0051] In this embodiment, the mass ratio of sheet graphene, carbon nanotubes, and lanthanum oxide is 5:3:1.5.

[0052] Example 4. This embodiment provides a special die-casting release agent for magnesium alloy automotive structural parts. The die-casting release agent comprises the following raw materials in parts by weight: 36 parts silicone oil, 16 parts modified volcanic ash, 4 parts silane coupling agent, 4 parts fatty alcohol polyoxyethylene ether, 3 parts antioxidant, and 22 parts deionized water.

[0053] In this embodiment, the silane coupling agent is silane coupling agent KH560; the antioxidant is antioxidant 1010.

[0054] The method for preparing the modified pozzolanic in this embodiment is as follows: S01: Preheat the volcanic ash at 56℃ for 1 hour, then ball mill the preheated volcanic ash and sodium alginate at a weight ratio of 7:5 for primary treatment. After ball milling, a combined volcanic ash-sodium alginate solution is obtained. S02: Volcanic ash-sodium alginate combined liquid and modified additives are further ball-milled at a weight ratio of 9:5. After ball milling, the mixture is filtered and dried to obtain modified volcanic ash.

[0055] Preferably, the ball milling speed for the first stage of ball milling is 1100 r / min, and the milling time is 2 h; the ball milling speed for the second stage of ball milling is 760 r / min, and the milling time is 1 h.

[0056] The preparation method of sodium alginate in this embodiment is as follows: S01a: Add 4 parts of sodium lignosulfonate solution and 3 parts of sodium alginate powder to 6 parts of barium nitrate solution and stir thoroughly to obtain sodium alginate solution; S02b: Mix 5 parts of silica, 2 parts of nano silica sol, 2 parts of sodium silicate solution with a mass fraction of 8% and 8 parts of kaolin to obtain kaolin liquid. Sodium alginate solution and kaolin solution were mixed at a weight ratio of 5:3 and ball-milled at a speed of 1070 r / min for 2 hours. After ball milling, the mixture was filtered and dried to obtain sodium alginate solution.

[0057] In this embodiment, the sodium lignosulfonate solution has a mass fraction of 12%; the barium nitrate solution has a mass fraction of 3%.

[0058] The modified additive in this embodiment is prepared by: sintering sheet graphene, carbon nanotubes and lanthanum oxide together, and obtaining the modified additive after sintering.

[0059] In this embodiment, the sintering temperature for the blending sintering process is 360°C, and the sintering time is 1 hour.

[0060] In this embodiment, the mass ratio of sheet graphene, carbon nanotubes, and lanthanum oxide is 5:3:1.

[0061] Comparative Example 1. Unlike Example 3, no modified volcanic ash was added.

[0062] Comparative Example 2. Unlike Example 3, sodium alginate was not added to the modified volcanic ash.

[0063] Comparative Example 3. Unlike Example 3, no kaolin solution was added to the sodium alginate agent.

[0064] Comparative Example 4. Unlike Example 3, no silica or nano-silica sol was added to the kaolin liquid.

[0065] Comparative Example 5. Unlike Example 3, no modified additives were added.

[0066] Comparative Example 6. Unlike Example 3, the preparation method of the modified additive is different, and carbon nanotubes and lanthanum oxide were not added.

[0067] The product performance tests of Examples 1-4 and Comparative Examples 1-6 were conducted, and the test results are as follows:

[0068] As can be seen from Examples 1-4 and Comparative Examples 1-6, the product of the present invention can achieve coordinated improvement in demolding efficiency and demolding quality, while exhibiting significant continuous demolding stability. The product does not contain modified volcanic ash, nor does it contain sodium alginate. Furthermore, the sodium alginate does not contain kaolin solution, and the kaolin solution does not contain silica, nano-silica sol, or any other additives. Different preparation methods for these additives, including the absence of carbon nanotubes and lanthanum oxide, all contribute to a deterioration in the product's performance. Only the modified volcanic ash obtained using the method of this invention exhibits the most significant performance improvement. Other methods used as substitutes are not as effective as those of this invention.

[0069] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0070] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A magnesium alloy automobile structural member-specific die casting release agent characterized by comprising: The die-casting release agent comprises the following raw materials in parts by weight: 35-40 parts of silicone oil, 15-20 parts of modified volcanic ash, 3-5 parts of silane coupling agent, 3-5 parts of fatty alcohol polyoxyethylene ether, 2-4 parts of antioxidant, and 20-30 parts of deionized water.

2. The magnesium alloy automobile structural member-specific die casting release agent according to claim 1, characterized by, The silane coupling agent is silane coupling agent KH560, and the antioxidant is antioxidant 1010.

3. The magnesium alloy automobile structural member-specific die casting release agent according to claim 1, characterized by, The preparation method of the modified volcanic ash is: S01: The volcanic ash is preheated at 55-60℃ for 1h, and the preheated volcanic ash and sodium alginate agent are ball milled for first-stage treatment at a weight ratio of (7-11):5; after the ball milling, a volcanic ash-sodium alginate combined liquid is obtained; S02: The volcanic ash-sodium alginate combined liquid and modified additives are ball milled for second-stage treatment at a weight ratio of (8-12):5; after the ball milling, the modified volcanic ash is obtained by filtration and drying.

4. The magnesium alloy automobile structural member-specific die casting release agent according to claim 3, characterized by, The ball milling speed of the first-stage treatment is 1000-1500r / min, and the ball milling time is 2h; the ball milling speed of the second-stage treatment is 750-850r / min, and the ball milling time is 1h.

5. The magnesium alloy automobile structural member-specific die casting release agent according to claim 3, characterized by, The preparation method of the sodium alginate agent is: S01a: 3-5 parts of a lignin sulfonate sodium solution, 2-4 parts of sodium alginate powder, and 5-8 parts of a barium nitrate solution are stirred to obtain a sodium alginate liquid; S02b: 4-7 parts of silicon dioxide, 1-3 parts of nano silicon sol, 2-3 parts of a 8% sodium silicate solution, and 7-11 parts of kaolin are blended and stirred to obtain a kaolin liquid; The sodium alginate liquid and the kaolin liquid are mixed at a weight ratio of 5:3, ball milled at a speed of 1050-1100r / min for 2h, and then filtered and dried to obtain the sodium alginate agent.

6. The magnesium alloy automobile structural member-specific die casting release agent according to claim 5, characterized by The mass fraction of the lignin sulfonate sodium solution is 10-15%, and the mass fraction of the barium nitrate solution is 2-5%.

7. The magnesium alloy automobile structural member-specific die casting release agent according to claim 1, characterized by, The preparation method of the modified additives is: the sheet-shaped graphene, carbon nanotubes, and lanthanum oxide are blended and sintered, and then the modified additives are obtained.

8. The magnesium alloy automobile structural member-specific die casting release agent according to claim 7, characterized by, The sintering temperature of the blending and sintering treatment is 350-400℃, and the sintering time is 1h.

9. The magnesium alloy automobile structural member-specific die casting release agent according to claim 7, characterized by, The mass ratio of the sheet-shaped graphene, carbon nanotubes, and lanthanum oxide is (4-6):3:(1-2).

Images