CN101813151B - Production method of semimetal ceramic matrix air disc brake pad - Google Patents

Abstract

The invention discloses a semimetal ceramic matrix air disc brake pad of an air disc braking system for heavy-duty freight cars and a production method thereof, wherein the production flow is as follows: sequentially weighing and putting 10 nonmetal assorted fibre, 35-40 metal fibre, 20 or 25 of friction performance regulator, 15-25 of vitrified bond, 5-10 of elastic toughening agent and 10 of filler into a high-speed mixer to mix uniformly, then carrying out pressing and thermocuring treatment according to a dry once-through molding technique of the traditional resin matrix friction materials, finally machining, ceramic processing, inspecting and packaging. The semimetal ceramic matrix air disc brake pad manufactured according to the technique has large braking torque, comfortable emergency braking, small heat fading and simple production technology, is environmental friendly, is particularly suitable for air disc brakes of the heavy-duty freight cars, and has wide market prospect.

Description

A kind of method for preparing semimetal ceramic matrix air disc brake pad

Technical field

The present invention relates to a kind of method for preparing semimetal ceramic matrix air disc brake pad.

Background technique

From technical standpoint, one, drum brake since its structural feature the heat of its generation of when work difficulty distribute, the press disc type break is because the brake disc major part all is exposed in the air, and heat exchange is easy, during work temperature rise lower, heat fade is little.Two, air-pressure disc brake is under the identical situation of required braking moment, and its boundary dimension is more much smaller than drum brake. and therefore arrange to car load and brought convenience; And since its quality particularly the quality of rotating part is much smaller, unbalance amount is also much smaller.Can obviously improve travelling comfort, smoothness and the control stability of automobile.Three, thickness reaches 20mm because the friction facing of air-pressure disc brake can wear and tear, and the worn and torn thickness of drum brake friction plate is less than 10mm, therefore under equal service condition, the replacement cycle of disk type braker friction facing is much longer than drum brake: if consider the difference of two kinds of brake cooling capacitys, their replacement cycle difference can reach more than 3 times.

In view of the performance characteristics more than the air-pressure disc brake, we can say that the application of disk type braker is the effective ways that solve the malfunctioning problem of automobile brake that China's heavy-duty freight car causes in the continuous descending process of mountain road.

The air-pressure disk type brake pad of main flow adopts resin-matrix friction material more in the market.Prescription characteristics from brake block, the temperature on brake block and brake disc surface is up to 500～700 ℃ during automobile brake, because the resin base brake block at high temperature can decompose and emit water, gas, wet goods, form thin film at friction surface, make dry friction become mixed friction or wet friction, friction factor significantly reduces, the hidden danger that exists brake to lose efficacy is simultaneously because a large amount of thermolysiss of resin have reduced its cementation, material at high temperature wearing and tearing aggravation causes significantly reduce the working life of brake block.Some ceramic automobile brake blocks on the market adopt the ceramic fiber of more amount to substitute traditional Steel Fibre at present, although its braking comfort property (comprise noise, fall ash and with the antithesis matching etc.) obviously improve, but owing to still adopt resin as main Bond, caused it to have the elevated temperature heat decline and at high temperature very easily cracked and problems such as high-temperature wear behavior is relatively poor.

Summary of the invention

Technical problem to be solved by this invention provides the method for preparing semimetal ceramic matrix air disc brake pad that a kind of braking ability is reliable, heat fade is little, travelling comfort is good.

In order to solve the problems of the technologies described above, the method for preparing semimetal ceramic matrix air disc brake pad provided by the invention, wherein, the prescription of each material of described semimetal ceramic matrix air disc brake pad calculates according to weight percentage: sodium aluminosilicate 15, aramid fibre pulp 5, carbon fiber 5, aluminum fiber 10, Steel Fibre 25, red copper fiber 5, antimony sulphide 5, chromite 5, artificial graphite 5, crystalline flake graphite 5, nitrile butadiene rubber 5, friction powder 5, vermiculite 5; Wherein aramid fibre pulp and carbon fiber are formed nonmetal mixed fibre, and antimony sulphide, chromite, artificial graphite and crystalline flake graphite are formed frictional property regulator;

Described method comprises the steps:

(1), batch mixing: the order that load weighted each material is dropped in the high speed mixer is: earlier nonmetal mixed fibre, frictional property regulator are carried out premixing, guarantee that nonmetal mixed fibre is in homogeneously dispersed state, add other former auxilliary material then, evenly stir;

(2), hot pressing: pressing pressure 200～300kgf/cm ², 150～160 ℃ of hot pressing temperatures, exhaust 5～8 times, the dwell time decides according to the thickness of brake block, is 55～65s/mm;

(3), the brake block after the moulding was warmed up to 200～220 ℃ at 5.5～6.5 hours from room temperature, be incubated 4～8 hours, cool to room temperature then with the furnace;

(4), the brake block after the heat treatment is carried out plain grinding, boring by technical requirements, then 300～400 ℃ temperature under carry out ceramic treatment, spraying, seal mark, check, packing.

Adopt the method for preparing semimetal ceramic matrix air disc brake pad of technique scheme, be on the basis of traditional asbestos and resin base brake block, in conjunction with the heavy-duty freight car characteristics, proposed semimetal ceramic matrix air disc brake pad, had that braking moment is big, emergency braking is comfortable steadily, do not have obviously decline, noise free, fall that ash and production technology are simple, environmental protection less.

In sum, the present invention is a kind of method for preparing semimetal ceramic matrix air disc brake pad that is applicable to the heavy-duty freight car disk braking system, has vast market prospect.

Embodiment

Further specify the effect of this invention below in conjunction with embodiment.

Embodiment 1:

Concrete preparation method is as follows:

(1), batch mixing: the order that load weighted each material is dropped in the high speed mixer is: earlier nonmetal, compound fibric, frictional property regulator are carried out premixing, guarantee that composite fiber is in homogeneously dispersed state, add other raw and auxiliary material then, evenly stir;

(2), hot pressing: pressing pressure 250kgf/cm ², 155 ℃ of hot pressing temperatures, exhaust 6 times, the dwell time is 60s/mm;

(3), the brake block after the moulding was warmed up to 210 ℃ at 6 hours from room temperature, be incubated 6 hours, cool to room temperature then with the furnace;

(4), the brake block after the heat treatment is carried out plain grinding, boring by technical requirements, then 350 ℃ temperature under carry out ceramic treatment, spraying, seal mark, check, packing.

The performance of semimetal ceramic matrix air disc brake pad

Respectively semimetal ceramic-base brake block sample and the exemplar of the Wuhan Yuan Feng DR01 of embodiment's 1 preparation are tested and estimated by GB5763-2008, QC/T479-1999 and QC/T239-1997, experimental result sees Table 1 and table 2.

Table 1 sample constant speed survey report

Table 2 DA225 exemplar is at Wuhan Yuan Feng air-pressure disc brake survey report

Attached one: the potency test key data

Annex II: heat fade and stable key data

Embodiment 2:

Concrete preparation method is as follows:

(1), batch mixing: the order that load weighted each material is dropped in the high speed mixer is: earlier nonmetal, compound fibric, frictional property regulator are carried out premixing, guarantee that composite fiber is in homogeneously dispersed state, add other raw and auxiliary material then, evenly stir;

(2), hot pressing: pressing pressure 200kgf/cm ², 150 ℃ of hot pressing temperatures, exhaust 5 times, the dwell time is 55s/mm;

(3), the brake block after the moulding was warmed up to 200 ℃ at 5.5 hours from room temperature, be incubated 4 hours, cool to room temperature then with the furnace;

(4), the brake block after the heat treatment is carried out plain grinding, boring by technical requirements, under 300 ℃ temperature, carry out ceramic treatment then, spraying, seal mark, check, packing.

The performance of semimetal ceramic matrix air disc brake pad

Respectively semimetal ceramic-base brake block sample and the exemplar of the Wuhan Yuan Feng DR01 of embodiment's 2 preparations are tested and estimated by GB5763-2008, QC/T479-1999 and QC/T239-1997, experimental result sees Table 3 and table 4.

Table 3 sample constant speed survey report

Table 4 DA225 exemplar is at Wuhan Yuan Feng air-pressure disc brake survey report

Attached one: the potency test key data

Annex II: heat fade and stable key data

Embodiment 3

Concrete preparation method is as follows:

(1), batch mixing: the order that load weighted each material is dropped in the high speed mixer is: earlier nonmetal, compound fibric, frictional property regulator are carried out premixing, guarantee that composite fiber is in homogeneously dispersed state, add other raw and auxiliary material then, evenly stir;

(2), hot pressing: pressing pressure 200kgf/cm ², 150 ℃ of hot pressing temperatures, exhaust 5 times, the dwell time is 55s/mm;

(3), the brake block after the moulding was warmed up to 200 ℃ at 5.5 hours from room temperature, be incubated 4 hours, cool to room temperature then with the furnace;

(4), the brake block after the heat treatment is carried out plain grinding, boring by technical requirements, under 300 ℃ temperature, carry out ceramic treatment then, spraying, seal mark, check, packing.

Claims (1)

1. method for preparing semimetal ceramic matrix air disc brake pad is characterized in that: wherein, the prescription of each material of described semimetal ceramic matrix air disc brake pad calculates according to weight percentage and is: sodium aluminosilicate 15, aramid fibre pulp 5, carbon fiber 5, aluminum fiber 10, Steel Fibre 25, red copper fiber 5, antimony sulphide 5, chromite 5, artificial graphite 5, crystalline flake graphite 5, nitrile butadiene rubber 5, friction powder 5, vermiculite 5; Wherein aramid fibre pulp and carbon fiber are formed nonmetal mixed fibre, and antimony sulphide, chromite, artificial graphite and crystalline flake graphite are formed frictional property regulator;

Described method comprises the steps:

(1), batch mixing: the order that load weighted each material is dropped in the high speed mixer is: earlier nonmetal mixed fibre, frictional property regulator are carried out premixing, guarantee that nonmetal mixed fibre is in homogeneously dispersed state, add other former auxilliary material then, evenly stir;

(2), hot pressing: pressing pressure 200～300kgf/cm ², 150～160 ℃ of hot pressing temperatures, exhaust 5～8 times, the dwell time decides according to the thickness of brake block, is 55～65s/mm;

(3), the brake block after the moulding was warmed up to 200～220 ℃ at 5.5～6.5 hours from room temperature, be incubated 4～8 hours, cool to room temperature then with the furnace;

(4), the brake block after the heat treatment is carried out plain grinding, boring by technical requirements, then 300～400 ℃ temperature under carry out ceramic treatment, spraying, seal mark, check, packing.