Surface wear-resistant treatment method for ceramic-based friction block
阅读说明：本技术 一种陶瓷基摩擦块的表面耐磨处理方法 (Surface wear-resistant treatment method for ceramic-based friction block ) 是由 蒋仁平 于 2019-09-04 设计创作，主要内容包括：本发明主要涉及汽车零件加工技术领域,公开了一种陶瓷基摩擦块的表面耐磨处理方法,包括：喷砂、浸泡、加热、一次渗氮、二次渗氮、渗硫、后处理；本发明提供的陶瓷基摩擦块的表面耐磨处理方法,方法简单,能够明显提高提高陶瓷基摩擦块的强度和耐磨性,减缓频繁刹车对摩擦块的损伤,延长摩擦块的使用寿命,保持较好的制动效果,提高驾驶安全系数。(The invention mainly relates to the technical field of automobile part processing, and discloses a surface wear-resistant treatment method of a ceramic-based friction block, which comprises the following steps: sand blasting, soaking, heating, primary nitriding, secondary nitriding, sulfurizing and post-treatment; the surface wear-resistant treatment method for the ceramic-based friction block provided by the invention is simple, can obviously improve the strength and wear resistance of the ceramic-based friction block, slows down the damage of frequent braking to the friction block, prolongs the service life of the friction block, keeps a better braking effect and improves the driving safety coefficient.)
1. The surface wear-resistant treatment method of the ceramic-based friction block is characterized by comprising the following steps of:
(1) performing sand blasting on the formed ceramic-based friction block, performing sand blasting by using carborundum under the pressure of 1.2 ~ 1.4.4 MPa by using compressed air as power to obtain a sand blasting piece;
(2) soaking, namely ultrasonically cleaning the sand blasting piece by using clear water, placing the sand blasting piece into a soaking solution, soaking for 8 ~ 10h at the temperature of 2 ~ 6 ℃, and standing and soaking for 6 ~ 8h at the temperature of 90 ~ 95 ℃ to obtain a soaked piece;
(3) heating, namely putting the soaked part in a heating furnace, heating to 160 ~ 180 ℃ at the speed of 2 ~ 3 ℃/min to 180 ℃, preserving heat for 40 ~ 50min, continuing to heat to 270 ~ 310 ℃ at the speed of 90 ~ 120min, rapidly cooling to 210 ~ 230 ℃, preserving heat for 60 ~ 90min, heating to 380 ~ 420 ℃ at the speed of 4 ~ 5 ℃/min, preserving heat for 40 ~ 50min, and naturally cooling to room temperature to obtain a heating element;
(4) a step of primary nitriding, which is to place the heating element in a vacuum furnace, heat the heating element to 260 ~ 300 ℃ at the speed of 3 ~ 4 ℃/min, preserve the heat for 50 ~ 60min, heat the heating element to 520 ~ 560 ℃ at the speed of 2 ~ 3 ℃/min, introduce primary ammonia gas, and keep the temperature for 2 ~ 3h to obtain a primary nitriding part;
(5) secondary nitriding, namely naturally reducing the temperature to 410 ~ 450 ℃ after the primary nitriding, introducing secondary ammonia gas, and keeping the temperature for 4 ~ 5h to obtain a secondary nitriding part;
(6) sulfurizing, namely introducing hydrogen sulfide when the temperature of the secondary nitriding part is reduced to 230 ~ 270 ℃, keeping the temperature for 3 ~ 4h, and naturally reducing the temperature to room temperature to obtain a sulfurizing part;
(7) and (3) post-treatment: and gluing the sulfurizing piece to obtain the wear-resistant ceramic-based friction block.
2. The method for surface abrasion resistance treatment of ceramic-based friction block according to claim 1, wherein the carborundum of step (1) has a grain size of 0.3 ~ 0.5.5 mm.
3. The method for performing surface abrasion resistance treatment on the ceramic-based friction block according to claim 1, wherein the soaking solution in the step (2) comprises the following raw materials, by weight, 11 ~ 13 parts of ethyl orthosilicate, 17 ~ 19 parts of butyl titanate and 74 ~ 78 parts of ethanol.
4. The method for treating the surface of the ceramic-based friction block according to claim 1, wherein the temperature is rapidly reduced in the step (3) at a rate of 5 ~ 6 ℃/min.
5. The method for surface abrasion resistance treatment of ceramic-based friction block according to claim 1, wherein the flow rate of the primary ammonia gas of step (4) is 7 ~ 9m3/h。
6. The method for surface abrasion resistance treatment of ceramic-based friction block according to claim 1, wherein the flow rate of secondary ammonia gas of step (5) is 2.4 ~ 2.8.8 m3/h。
7. The method for surface abrasion resistance treatment of ceramic-based friction block according to claim 1, wherein the hydrogen sulfide of step (6) has a flow rate of 3.3 ~ 3.7.7 m3/h。
8. A wear-resistant ceramic-based friction block prepared by the method for performing surface wear-resistant treatment on the ceramic-based friction block according to any one of claims 1 ~ 7.
Technical Field
The invention mainly relates to the technical field of automobile part machining, in particular to a surface wear-resistant treatment method for a ceramic-based friction block.
Background
The automobile is the important transportation and vehicle in society now, can promote industrial development fast, make things convenient for people's life, along with the constantly increasing of automobile quantity, the road is also more and more crowded, driving safety also receives more and more attention of people, the most important guarantee of driving safety is exactly the brake block, the brake block is also called the brake shoe, in the braking system of automobile, the brake block is the most critical safety part, the quality of all brake effects all is that the brake block plays decisive role, so say that the brake block that is good is the god of protection of people and car. The brake pad is composed of a steel plate, a bonding heat insulation layer and a friction block, the steel plate is coated for rust prevention, the heat insulation layer is composed of a non-heat-transfer material and aims at heat insulation, the friction block is composed of a friction material and an adhesive, and the friction block is extruded on a brake disc or a brake drum to generate friction during braking, so that the purpose of decelerating and braking the vehicle is achieved, the automobile can be braked to play a role of the friction block, and the quality of the friction block directly influences the braking effect of the automobile; according to the materials, the friction block can be divided into a metal friction block, an asbestos friction block, a resin friction block, a carbon-based friction block and a ceramic-based friction block, wherein the ceramic-based friction block is low in price, high in performance price and widely used gradually, but the wear-resistant effect of the ceramic-based friction block is still to be further improved after the ceramic-based friction block is applied in the market shortly; the ceramic-based friction block is not pure ceramic, is prepared by mixing ceramic fiber with a small amount of metal raw materials and adding other additives, tests are carried out on the raw materials of the friction block at present in order to improve the wear resistance of the ceramic-based friction block, the wear resistance of the friction block is improved by changing the raw material composition and the preparation method, and the wear resistance of the ceramic-based friction block is not improved on the basis of not changing the raw material composition.
Disclosure of Invention
In order to make up for the defects of the prior art, the invention aims to provide a surface wear-resistant treatment method for a ceramic-based friction block.
A surface wear-resistant treatment method of a ceramic-based friction block comprises the following steps:
(1) performing sand blasting on the formed ceramic-based friction block, performing sand blasting by using carborundum under the pressure of 1.2 ~ 1.4.4 MPa by using compressed air as power, so that the carborundum forms a uniform and fine concave-convex surface on the surface of the ceramic block, the friction force between the friction block and a brake drum can be increased, the braking effect is improved, meanwhile, the fine concave-convex surface is beneficial to the permeation and adhesion of chemical components in the post-treatment process, the treatment effect is improved, and a sand blasting piece is obtained;
(2) soaking, namely ultrasonically cleaning a sand blasting piece by using clear water, placing the sand blasting piece into a soaking solution, soaking for 8 ~ 10h at the temperature of 2 ~ 6 ℃, standing and soaking for 6 ~ 8h at the temperature of 90 ~ 95 ℃, soaking at a low temperature firstly, and soaking at a high temperature, wherein the soaking solution contains a plurality of high molecular organic compounds, can permeate into a friction block through a concave-convex surface, promotes metal components in the friction block to be tightly bonded with ceramic fibers, ensures that the structure is more compact, and can improve the wear resistance of the friction block to obtain a soaked piece;
(3) heating, namely putting the soaked piece into a heating furnace, heating to 160 ~ 180 ℃ at the speed of 2 ~ 3 ℃/min, preserving heat for 40 ~ 50min, continuing to heat to 270 ~ 310 ℃ at the speed of 90 ~ 120min, quickly cooling to 210 ~ 230 ℃ at the speed of 60 ~ 90min, heating to 380 ~ 420 ℃ at the speed of 4 ~ 5 ℃/min, preserving heat for 40 ~ 50min, naturally cooling to room temperature, slowly increasing the temperature twice, quickly cooling and heating, refining a metal crystal structure, increasing the contact surface of metal components and ceramic fibers, improving the bonding fastness, and enhancing the strength and wear resistance of a friction block to obtain a heating piece;
(4) a step of primary nitriding, which is to place the heating element in a vacuum furnace, heat the heating element to 260 ~ 300 ℃ at the speed of 3 ~ 4 ℃/min, preserve the heat for 50 ~ 60min, heat the heating element to 520 ~ 560 ℃ at the speed of 2 ~ 3 ℃/min, introduce primary ammonia gas, and keep the temperature for 2 ~ 3h to obtain a primary nitriding part;
(5) after the primary nitriding is carried out, naturally reducing the temperature to 410 ~ 450 ℃, introducing secondary ammonia gas, keeping the temperature for 4 ~ 5h, enabling the nitrogen gas to slowly permeate, fully combining with metal components, reducing the brittleness of the metal components, improving the toughness and the wear resistance, enabling ceramic fibers to stably exist under the condition that the metal components are not worn, and improving the strength and the wear resistance of a friction block to obtain a secondary nitriding part;
(6) sulfurizing, namely after the temperature of a secondary nitriding part is reduced to 230 ~ 270 ℃, introducing hydrogen sulfide, keeping the temperature for 3 ~ 4h, keeping the flow rate at first and then at a low flow rate, slowly permeating nitrogen, fully combining with metal components, reducing the brittleness of the metal components, improving the toughness and the wear resistance, enabling ceramic fibers to stably exist under the condition that the metal components are not abraded, improving the strength and the wear resistance of a friction block, and naturally cooling to room temperature to obtain a sulfurizing part;
(7) and (3) post-treatment: and gluing the sulfurizing piece to obtain the wear-resistant ceramic-based friction block.
The carborundum of the step (1) has the grain diameter of 0.3 ~ 0.5.5 mm.
The soaking solution in the step (2) is prepared from the following raw materials, by weight, 11 ~ 13 parts of ethyl orthosilicate, 17 ~ 19 parts of butyl titanate and 74 ~ 78 parts of ethanol.
And (4) rapidly cooling in the step (3), wherein the cooling speed is 5 ~ 6 ℃/min.
The flow rate of the primary ammonia gas in the step (4) is 7 ~ 9m3/h。
The flow rate of the secondary ammonia gas in the step (5) is 2.4 ~ 2.8.2.8 m3/h。
The flow rate of the hydrogen sulfide in the step (6) is 3.3 ~ 3.7.7 m3/h。
The wear-resistant ceramic-based friction block is prepared by the surface wear-resistant treatment method of the ceramic-based friction block.
The invention has the advantages that: the surface wear-resistant treatment method for the ceramic-based friction block is simple, can obviously improve the strength and the wear resistance of the ceramic-based friction block, slows down the damage of frequent braking to the friction block, prolongs the service life of the friction block, keeps a better braking effect and improves the driving safety coefficient; firstly, the formed ceramic-based friction block is subjected to sand blasting, so that uniform and fine concave-convex surfaces are formed on the surface of the ceramic block by carborundum, the friction force between the friction block and a brake drum can be increased, the braking effect is improved, meanwhile, the fine concave-convex surfaces are beneficial to the permeation and adhesion of chemical components in the post-treatment process, and the treatment effect is improved; after sand blasting, the friction block is placed in a soaking solution, low-temperature soaking is firstly carried out, then high-temperature soaking is carried out, the soaking solution contains various high-molecular organic compounds, and the high-molecular organic compounds can permeate into the friction block through the concave-convex surface, so that the metal components in the friction block are promoted to be tightly bonded with the ceramic fibers, the structure is more compact, and the wear resistance of the friction block can be improved; after soaking, the friction block is heated in stages, the temperature is slowly increased twice, and then the temperature is rapidly reduced and increased, so that the metal crystal structure can be refined, the contact surface of metal components and ceramic fibers is increased, the bonding firmness is improved, and the strength and the wear resistance of the friction block are enhanced; nitriding the friction block twice, wherein the nitriding is carried out on the friction block at a large flow rate and then at a small flow rate, so that nitrogen can slowly permeate and is fully combined with metal components, the brittleness of the metal components can be reduced, the toughness and the wear resistance can be improved, ceramic fibers can stably exist under the condition that the metal components are not worn, and the strength and the wear resistance of the friction block can be improved; and sulfurizing treatment is carried out after nitriding, a protective film is formed on the metal surface, the damage to the friction block in the brake and braking process is avoided, the wear resistance of the ceramic-based friction block is improved, the service life is prolonged, and the driving safety is improved.
Detailed Description
The invention is illustrated by the following specific examples.