CN100447181C - Environment-friendly high-performance automobile brake pad and preparation method thereof - Google Patents

Abstract

The invention relates to the production of special products with plastic state substances, specifically automobile brake materials and its preparation process, which is characterized in that: adhesives, reinforcing fibers, friction performance regulators, and inorganic fillers are mixed according to the ratio, and the use of durable The high-temperature coupling agent surface treatment, the environmentally friendly high-performance automobile brake pads made by hot pressing, replace the automobile brake pads made of asbestos fibers, overcome the high-temperature recession defects of asbestos automobile brake pads, and improve the performance of brake pads. Excellent overall friction performance prolongs its service life, reduces operating costs and purifies the environment.

Description

Environment-friendly high-performance automobile brake pad and preparation method thereof

Technical field:

The present invention relates to the production of special products with substances in plastic state, specifically automobile brake materials and its preparation process.

Background technique:

With the increase of vehicle speed, load capacity, and environmental protection awareness, the automotive industry has also put forward higher and higher requirements for the comprehensive performance of brake pads. Automobile brake pads made of asbestos, in the high temperature state (about 300 ℃) generated after emergency braking, the friction coefficient will be seriously reduced, resulting in serious degradation of braking torque, affecting driving safety; and short service life, frequent replacement , which not only leads to high operating costs, but also dehydrated asbestos dust formed under high temperature wear, which has a strong carcinogenic effect on the human body and pollutes the environment.

Invention content:

The object of the present invention is to: provide a kind of method to prepare environment-friendly high-performance automobile brake pad, replace the automobile brake pad made of asbestos fiber, to overcome the high-temperature decay defect of asbestos automobile brake pad, improve the overall friction performance of the brake pad, Extend its service life, reduce operating costs, and purify the environment.

The preparation method of the environment-friendly high-performance automobile brake pad of the present invention is to mix adhesives, reinforcing fibers, friction performance regulators, and inorganic fillers according to the proportion, and use high-temperature-resistant coupling agents for surface treatment. The specific process steps are as follows:

A: Ingredients, mixing:

Batch each component according to the formula, and then use a special mixer for dry mixing to ensure that the fibers are fully dispersed and uniform, and the mixture is prepared for use; the mixing time is controlled: 5 to 40 minutes.

B: Hot pressing molding:

It adopts positive pressure method to press and form in the metal mold, and controls the parameter process:

Temperature: 160±5℃;

Pressure: 20±10%Mpa;

Deflation times: 4 to 6 times;

Holding time: 1 to 8 minutes.

C: heat treatment:

The hot-pressed product is then subjected to heat treatment to promote the adhesive to achieve the best bonding state. The treatment process is as follows:

D: Grinding: Use dry grinding equipment to process the product to the size specified in the drawing.

E: Surface spraying: Use spraying equipment to coat the non-friction surface of the product with an anti-rust coating.

F: Printing and packaging: According to user requirements, print specific labels and pack them for use.

The composition of the environment-friendly high-performance automobile brake pad of the present invention is by weight percentage:

4-15% of binder, 10-48% of reinforcing fiber, 5-40% of friction modifier, and 10-60% of inorganic filler.

The preparation method of the environment-friendly type high-performance automobile brake pad of the present invention, its composition is:

Adhesives are: phenolic resin, polyurethane resin, epoxy resin;

Reinforced fibers are: steel fiber, copper fiber, aluminum fiber, aramid fiber, polyester fiber, carbon fiber, hemp fiber, paper fiber, cellulose fiber, sprayed rock wool fiber, aluminum silicate fiber, glass fiber, silica fume fiber , KFK composite fiber, etc.;

The friction modifier is: powder with Mohs hardness greater than 4.5, such as: chromite, quartz sand, alumina, silicon carbide, feldspar, magnetite, pyrite, zircon, etc.; organic toughening powder , such as: NBR, tire powder, organic friction agents, etc.;

Various solid powder lubricants include soft metals, artificial graphite, natural graphite, molybdenum disulfide, etc.;

Inorganic fillers are: ceramic powder with Mohs hardness less than 4, such as: barium sulfate, antimony sulfide, kaolin, bentonite, fluorite, calcium carbonate, talcum powder, dolomite, gypsum, mica, vermiculite, coral rock, etc.

The environment-friendly high-performance automobile brake pad prepared by the method of the present invention overcomes the high-temperature decay defect of the asbestos automobile brake pad, improves the overall friction performance of the brake pad, replaces the automobile brake pad made of asbestos fiber, and prolongs its life. Long service life, reduced operating costs, and purified the environment.

The specific manifestation is as follows:

A. Features of the invention

(1) Use a variety of non-asbestos fibers to replace asbestos fibers with good dispersibility and affinity, and use a variety of unique high-temperature-resistant coupling agent treatment technologies to solve the affinity (wettability) between non-asbestos fibers and the matrix ) problem; combined with the special design of the internal structure of the mixer, it overcomes the problem of clustering of composite non-asbestos fibers during the mixing process, makes the fibers well dispersed during the mixing process, and solves the insufficient internal resistance of the brake pad caused by the above problems, Unstable friction performance and other defects.

(2) Due to the inherent high-temperature thermal decomposition characteristics of resin, if the resin content in automobile friction materials is too high, the high-temperature recession will be serious; if the resin content is too low, the overall strength will not be enough. Using the unique low-content resin matrix technology, combined with strengthening rubber cross-linking and anti-aging treatment, it not only solves the material toughness of the product, but also improves the high-temperature decay resistance, internal shear strength, and anti-aging performance of the material.

(3) Use modern analysis technology to conduct basic research and analysis on the thermal characteristics and phase transition of raw materials, and screen raw materials according to the research results. The formula adopts components with good thermal stability and less phase change, such as precipitated barium sulfate, silica fume cotton, dolomite and other key fillers, which improve the high temperature resistance of the brake pad; use surface coupling technology to increase the filler and resin The compatibility of the matrix solves the problem of composite strengthening of the matrix, fiber and filler, and improves the service life of the brake pad.

(4) Graphite material can reduce the wear of brake pads, reduce brake noise, and increase brake stability. However, when it is above 450°C, it will oxidize rapidly, causing problems such as high temperature decay and increased wear. The unique multi-component lubrication technology solves the problem of friction interface diaphragm and carbon deposition, which not only plays a role in lubrication, but also does not cause high-temperature thermal degradation, and at the same time improves the wear resistance of brake pads.

(5) Premix and granulate porous raw materials such as hollow microsphere structure powder (such as coal ash) and expanded anthill stone with a high-temperature-resistant binder to prepare unique powder porous composite particles and apply them to brake pads. It achieves the effects of reducing the proportion of brake pads, reducing costs, suppressing brake noise, and reducing high-temperature fading, and improving the comprehensive performance of brake pads as a whole. The asbestos-free brake pads produced by domestic and foreign automobiles generally have the problems of large high-temperature decay, poor toughness of material processing, and insufficient strength, and their service life is equivalent to that of similar foreign products.

(6) Through basic research, a large number of domestic raw materials with abundant resources and cheap prices are used, and the production cost is greatly reduced through process optimization and simplification of the production process. The market price of the product is only equivalent to 30% of similar imported products, which has great advantages Strong international and domestic market competitiveness.

B. the product performance that the present invention produces and the comparison of traditional asbestos product performance

The newly developed high-performance, environmentally friendly brake pads replace asbestos products. The brake materials do not contain harmful ingredients, have no pollution to the environment, and have excellent resistance to high temperature and heat decay. The brakes are sensitive, smooth, and there is no brake squeal. , can meet the high-speed, high-load operation safety of automobiles, and the service life is increased to more than 2 to 3 times that of asbestos products

Performance comparison of asbestos and non-asbestos brake pads (Dongfeng EQ153 commercial vehicle)

It can be seen from the above data that the asbestos-free brake pads developed by Central South University and Boyun New Material Co., Ltd. are far superior to asbestos products. But the cost is about 20% higher than that of asbestos products. Generally, the mixture cost of asbestos friction material is 3000-6000 yuan/ton, while the cost of non-asbestos friction material mixture is 4500-7000 yuan/ton. Taking Dongfeng EQ153 brake as an example, the price of asbestos sheet is 11 yuan/piece, high Performance, asbestos-free brake pads price: 14 yuan / piece. Therefore, compared with traditional asbestos brake pads, environmentally friendly, high-performance non-asbestos brake pads have a high performance-price ratio advantage.

It fundamentally solves the problem of composite strengthening of the matrix, non-asbestos fibers and the key friction performance modifier, and solves the high temperature decay resistance of the material, the strength and wear resistance of the brake pad; the use of multi-component lubrication technology overcomes the graphite Defects such as high temperature recession and increased wear caused by lubricating materials at high temperatures solve the problems of friction interface diaphragm and carbon deposition.

Description of drawings:

Fig. 1 is a schematic diagram of the technological process of the environmental-friendly high-performance automobile brake pad of the present invention.

Detailed ways:

A: Examples of Changan passenger car disc brake pads:

①According to the following formula ingredients:

Phenolic resin 9%; steel fiber 12%; brass fiber 5%; copper fiber 3%; aramid fiber 3%; glass fiber 5%; silica fume 6%; artificial graphite 5%; natural graphite 5%; ferrochrome 8% ore; 8% pyrite; 5% magnetite; 4% antimony sulfide; 10% barium sulfate; 5% dolomite; 3% calcium fluoride; 4% kaolin;

② Use a vertical mixer for mixing to ensure that the ingredients are evenly distributed;

③Use a hot press and specific tooling and molds to place the mixture in a mold according to a certain weight and press it into shape;

④ Use a high-power oven to cure the phenolic resin;

⑤ Carry out follow-up machining on the heat-treated product according to the drawing requirements;

⑥ Packing and storage.

B: Example of Dongfeng Motor EQ153 drum brake pad

① Formula:

Phenolic resin 15%; steel fiber 20%; brass fiber 5%; cellulose fiber 3%; glass fiber 5%; rock wool 5%; FKF fiber 3%; silica fume cotton 5%; artificial graphite 4%; natural graphite 6%; chromite 4%; magnetite 5%; pyrite 4%; quartz sand 3%; alumina 3%; kaolin 5%; bentonite 3%; vermiculite 2%.

② Use a vertical mixer for mixing to ensure that the ingredients are evenly distributed;

③Use a hot press and specific tooling and molds to place the mixture in a mold according to a certain weight and press it into shape;

④ Use a high-power oven to cure the phenolic resin;

⑤ Carry out follow-up machining on the heat-treated product according to the drawing requirements;

⑥ Packing and storage.

C; Santana car disc brake pad example

① Formula:

Phenolic resin 5%; steel fiber 20%; aramid fiber 2%; copper fiber 5%; brass fiber 3%; paper fiber 1%; antimony sulfide 7%; artificial graphite 15%; petroleum coke 6%; chromite 8%; alumina 2%; silica fume cotton 9%; barium sulfate 5%; dolomite 2%; vermiculite 3%; composite particles 7%.

② Use a vertical mixer for mixing to ensure that the ingredients are evenly distributed;

③Use a hot press and specific tooling and molds to place the mixture in a mold according to a certain weight and press it into shape;

④ Use a high-power oven to cure the phenolic resin;

⑤ Carry out follow-up machining on the heat-treated product according to the drawing requirements;

⑥ Packing and storage.

Claims (2)

1, a kind of environment-protection type high-performance automobile braking piece, it is characterized in that: composition is tamanori 4～15% by weight percentage, fortifying fibre 10～48%, frictional property regulator 5～40%, mineral filler 10～60%, wherein tamanori is phenolic resinoid, polyamine lipid resin or redix; Fortifying fibre is steel fiber, copper fiber, aluminum fiber, aramid fiber, polyster fibre, carbon fiber, flaxen fiber, paper fiber, cellulosic fibre, rockwool coating resin fiber, aluminum silicate fiber, glass fibre, silicon ash cotton fibre or KFK conjugated fibre; Frictional property regulator is a Mohs' hardness greater than 4.5 powder: chromite, quartz sand, aluminum oxide, silicon carbide, feldspar, magnetite, sulfurous iron ore, zircon, in soft metal, synthetic graphite, natural graphite, the molybdenumdisulphide in the solid powder shape lubricant one or more contain organic toughness reinforcing powder or other organic friction agents of paracril, tyre talc; Mineral filler is a Mohs' hardness less than 4 ceramic powder: barium sulfate, antimony sulfide, kaolin, wilkinite, fluorite, lime carbonate, talcum powder, rhombspar, gypsum, mica, vermiculite or coral rock.

2, a kind of preparation method of environment-protection type high-performance automobile braking piece according to claim 1, be to adopt tamanori, fortifying fibre, frictional property regulator, mineral filler to mix according to proportioning, utilize high temperature resistant coupling agent to carry out surface treatment, it is characterized in that:

A: batching, mixing

By prescription each composition is prepared burden, then, carry out dry type with vertical mixer and mix, guarantee that fiber fully disperses, evenly, it is stand-by to make compound; Control mixing time: 5～40 minutes;

B: hot pressing moulding

Adopt the compression moulding in metal die of malleation mode, controlled variable technology:

Temperature: 160 ± 5 ℃,

Pressure: 20 ± 10%Mpa,

The venting number of times: 4～6 times,

Dwell time: 1～8 minute;

C: thermal treatment

With the product after hot-forming, again through Overheating Treatment, treatment process is:

Room temperature heats up and to reach 110 ℃ in 1 hour, in this temperature insulation insulation in 1 hour to 180 ℃ 5 hours that heated up again in 2 hours, heat up 30 minutes 210 ℃, be incubated 1 hour;

D: ground finish

Utilize the ground finish of dry grinding equipment;

E: surface spraying

Utilize spraying equipment, the product non-rubbing surface is applied antirust coating;

F: seal mark, packing

Stamp sign, packed for standby use.

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