Background technology
The paper friction material general work is in the lubricating oil medium.In order to obtain good torsion pass and braking effect, paper friction material requires that higher thermostability is arranged, good physical and mechanical property, height and stable kinetic friction coefficient, lower static friction coefficient and less wear rate, and the acquisition of these performances depends on the composition of material, also depends on material interface weave construction, porosity and rebound resilience.So paper friction material is made up of fortifying fibre, frictional property regulator, binding agent and filler usually.Use in fortifying fibre and the binding agent at paper friction material, selectable fortifying fibre and binding agent kind are more, but their thermotolerance, snappiness, physical and mechanical property, friction and wear performance difference are bigger, adopt different fortifying fibres and binding agent can cause the difference of paper friction material on friction and wear behavior and physics/mechanical property.
When paper friction material general requirement of only considering to satisfy friction and wear behavior during as the automatic transmission friction sheets; But when using as the automatic gear-box brake strap owing to be in crooked working order for a long time, braking procedure to stand repeatedly radius-of-curvature change and draw, the pressure effect, pair friction and wear performance demands is not only arranged, also require material to have snappiness.
Document " Chinese patent CN1529068A " has been introduced a kind of polymer Composite Paper base frication material, its essentially consist weight percent is: resol 31~45%, xylon 20~30%, bamboo fibers 5~15%, carbon fiber 15~20%, graphite 5~10%, silica 1~5%, diatomite 2~5%, ferric oxide 1~3%.This is that the binding agent paper friction material becomes tridimensional network with resol behind resin solidification, makes that the snappiness of friction materials is relatively poor, reports that as yet can whether have enough snappinesies enough uses as the friction catch band.Though have research to improve the snappiness of resol in addition, still can not improve the snappiness of this paper friction material by a relatively large margin by cashew nut oil modified or additive method modification.
Document " Chinese patent CN1456589A " has been introduced a kind of paper friction material, it is characterized in that containing at least a kind of fiber, at least a filler and resin and conditioning agent are formed, the weight percentages of components of various compositions is: fiber 27-47%, filler 16-33%, resin 30-35%, conditioning agent 3-13%, described conditioning agent includes the rubber of 3-5%, does not report that as yet can whether have enough snappinesies can use as the friction catch band.
Document " CN85105905A " has been introduced a kind of oil-bath clutch rubber empiecement that uses rubber as binding agent, and the snappiness of this friction materials is better relatively, and frictional coefficient is higher.But this friction materials is quiet/and kinetic friction coefficient is than big, and moment of friction changes greatly with braking time, and friction stability is poor, and the thermotolerance of friction materials is relatively poor.
Summary of the invention
In order to overcome the deficiency of prior art paper friction material snappiness difference under crooked working order, the invention provides a kind of flexible-paper-base friction material, both had snappiness, had and have the good friction polishing machine.
The technical solution adopted for the present invention to solve the technical problems is: a kind of flexible-paper-base friction material, the flexible fortifying fibre that contains weight percent 3~7%, 5~20% carbon fiber, other fiber of 4~25%, 2~10% flexible adhesives, 20~44% fragility tackiness agent, 10~25% frictional property regulator, 15~30% filler.
Described flexible fortifying fibre is the pre-oxygen silk of Kevlar fiber, carbon fiber, or Kevlar fiber and the pre-oxygen silk of carbon fiber blend fiber.
Described carbon fiber is PAN-based carbon fiber, asphalt base carbon fiber, or PAN-based carbon fiber and asphalt base carbon fiber blend fiber.
Described other fiber is flexible mineral fiber, vegetable fibre, cellulosic fibre.
Described flexible adhesion agent is nitrile rubber, styrene-butadiene rubber(SBR), viton, silicon rubber.
Described fragility binding agent is resol, cashew nut oil modified alkyd resin, nitrile rubber modified phenolic resin, boron glue modified phenolic resins.
The invention has the beneficial effects as follows: since adopt flexible fortifying fibre and frictional behaviour preferably carbon fiber as the fortifying fibre of paper friction material, use flexible adhesion agent and fragility binding agent binding agent simultaneously as paper friction material, flexible fortifying fibre and properties of carbon complementation have improved the snappiness of paper friction material, have also improved the friction and wear behavior of paper friction material simultaneously; Flexible-paper-base friction material minimum bend radius-of-curvature according to formulation of the present invention is 6.0~6.8cm, not only has good snappiness but also have good mechanical intensity and thermotolerance.
The present invention is further described below in conjunction with embodiment.
Embodiment
Based on having linearity or nonlinear relationship between the over-all properties of matrix material and the component property, carbon fiber and flexible fortifying fibre are used with preferably if with frictional behaviour, fragility binding agent and flexible adhesion agent are used with, bring into play the performance advantage of different fibers and binding agent and realize the advantage performance complement, control the ratio of friction and wear behavior carbon fiber and snappiness fortifying fibre and fragility binding agent and flexible adhesion agent preferably simultaneously, make paper friction material both have good snappiness, have good friction and wear behavior again.
Embodiment 1: get flexible fortifying fibre: Kevlar fiber 3kg, carbon fiber: PAN-based carbon fiber 11kg, asphalt base carbon fiber 9kg, other fibers: cellulosic fibre 4kg, frictional property regulator 10kg, filler 15kg, flexible adhesion agent: 120 purpose acrylonitrile-butadiene rubber powder 2kg, fragility binding agent: nitrile rubber modified phenolic resin 20kg, according to copying the paper method above-mentioned materials is put in the suitable quantity of water, join behind the homodisperse and copy moulding in the paper equipment, the oven dry, cut into suitable friction plate size after, the dipping cashew nut oil modified alkyd resin-ethanolic soln make its quality percentage composition reach 26%, oven dry, in 170 ℃ of temperature, hot-press solidifying moulding under the pressure 7.0MPa obtains described flexible-paper-base friction material after the machining, the minimum bend radius-of-curvature of this flexible-paper-base friction material is 6.8cm; Adopt MM1000-II type frictional property test machine test kinetic friction coefficient 1.20~1.30, static friction coefficient 0.168, wear rate 6.0 * 10
-8Cm
3/ J; Violent weightless starting temperature is higher than 358 ℃.
Embodiment 2: get flexible fortifying fibre: the pre-oxygen silk of carbon fiber 3kg, carbon fiber: asphalt base carbon fiber 17kg, other fibers: vegetable fibre 22kg, frictional property regulator 13kg, filler 18kg, flexible adhesion agent: 180 purpose styrene butadiene rubber powder 4kg, fragility binding agent: resol 25kg, according to copying the paper method above-mentioned materials is put in the suitable quantity of water, join behind the homodisperse and copy moulding in the paper equipment, oven dry, after cutting into suitable friction plate size, spraying cashew nut oil modified alkyd resin-ethanolic soln makes its quality percentage composition reach 12.5%, oven dry, in 170 ℃ of temperature, hot-press solidifying moulding under the pressure 7.0MPa, obtain flexible-paper-base friction material after the machining, the minimum bend radius-of-curvature of this flexible-paper-base friction material is 6.0cm, adopts MM1000-II type frictional property test machine test kinetic friction coefficient 1.20~1.26, static friction coefficient 0.16, wear rate 7.4 * 10
-8Cm
3/ J, the weightless starting temperature of severe thermal is higher than 345 ℃.
Embodiment 3: get flexible fortifying fibre: Kevlar fiber 2kg, the pre-oxygen silk of carbon fiber 3kg, carbon fiber: PAN-based carbon fiber 14kg, other fibers: no asbestos deposit fibres 25kg, frictional property regulator 16kg, filler 21kg, flexible adhesion agent: 240 purpose viton powder 6kg, fragility binding agent: cashew nut oil modified alkyd resin 30kg, according to copying the paper method above-mentioned materials is put in the suitable quantity of water, joined behind the homodisperse and copy moulding in the paper equipment, oven dry, after cutting into suitable friction plate size, spraying glue, the hot-press solidifying moulding obtains flexible-paper-base friction material after the machining.
The prescription of embodiment 4~6 sees the following form.Silicon rubber has also been selected in the flexible adhesion agent for use; The fragility binding agent has also been selected boron modified phenolic resin for use.
For better explanation the present invention, below embodiment 1~6 is tabulated (unit in the table: kg).
Embodiment |
Flexible fiber |
Carbon fiber |
Other fiber |
The flexible adhesion agent |
The fragility binding agent |
Conditioning agent |
Filler |
Embodiment 1 |
3 |
20 |
4 |
2 |
20 |
10 |
15 |
Embodiment 2 |
4 |
17 |
22 |
4 |
25 |
13 |
18 |
Embodiment 3 |
5 |
14 |
25 |
6 |
30 |
16 |
21 |
Embodiment 4 |
5 |
11 |
18 |
6 |
35 |
19 |
24 |
Embodiment 5 |
6 |
8 |
12 |
8 |
40 |
22 |
27 |
Embodiment 6 |
7 |
5 |
9 |
10 |
44 |
25 |
30 |
Above-mentioned paper friction material uses machine hand's production of planting, use at least a flexible fortifying fibre and at least a carbon fiber fortifying fibre, use at least a flexible adhesion agent and at least a fragility binding agent binding agent simultaneously as paper friction material as paper friction material.The performance complement of carbon fiber and flexible fortifying fibre can make paper friction material both have good snappiness, has good friction and wear behavior simultaneously; Meanwhile, the performance complement of fragility tackiness agent and flexible adhesives can make paper friction material not only have good snappiness but also have good mechanical intensity and thermotolerance.
Through test of many times, flexible fortifying fibre can be selected Kevlar fiber, the pre-oxygen silk of carbon fiber separately for use, or the blend fiber of Kevlar fiber and the pre-oxygen silk of carbon fiber; Carbon fiber comprises PAN-based carbon fiber and asphalt base carbon fiber; Other fibers comprise flexible no asbestos deposit fibres, vegetable fibre or cellulosic fibre.The weight percentage of its composition is:
Flexible fortifying fibre 3~7%;
Carbon fiber 5~20%;
Other fiber 4~25%;
Flexible adhesion agent 2~10%;
Fragility binding agent 20~44%;
Frictional property regulator 10~25%;
Filler 15~30%;
In order to make described paper friction material satisfy the snappiness requirement, the quality percentage composition of flexible fortifying fibre is not less than 3.0%; For the moment of friction and the stable friction factor requirement that guarantee this paper friction material, the weight percentage of flexible fortifying fibre is not more than 7.0%, and the quality percentage composition of carbon fiber should be greater than 5.0% preferably for frictional behaviour.
The flexible adhesion agent is a rubber adhesive, comprises paracril, styrene-butadiene rubber(SBR), viton, silicon rubber, and grain diameter is between 120~240 orders; The fragility binding agent is a resol class binding agent, comprises resol, cashew nut oil modified alkyd resin, nitrile rubber modified phenolic resin, boron modified phenolic resin.
In order to make this paper friction material obtain corresponding snappiness, the quality percentage composition of flexible adhesion agent should be greater than 2.0%, but moment of friction and stable friction factor in order to guarantee friction materials, the quality percentage composition of flexible adhesion agent should be less than 10.0%; In order to guarantee that this friction materials has corresponding mechanics intensity and good thermotolerance, the quality percentage composition of fragility binding agent should be greater than 20%.
The frictional property regulator choosing can be selected graphite, MoS for use
2Powder, sulfuration antimony powder, Al
2O
3, SiC
4, BN, chromite powder, organic friction powder, zircon sand powder etc.Filler is selected BaSO for use
4, conventional substances such as kaolin, diatomite.
In order to make described flexible-paper-base friction material obtain snappiness and friction and wear behavior preferably, its flexible fiber, carbon fiber, flexible adhesion agent and fragility binding agent by force can partly or entirely mix use.