Brake Pad Formulation - Friction Material
1. The composition of the friction material
Friction material belongs to polymer ternary composite material, which consists of three parts: polymer compound as binder; inorganic or organic fiber as reinforcing component; filler as friction performance regulator or compounding agent.
1. Organic binder
The organic binders used in friction materials are phenolic resins and synthetic rubbers, and phenolic resins are the main ones. Their characteristics and functions are that when they are at a certain heating temperature, they first soften and then enter a viscous flow state, generate flow and evenly distribute in the material to form a matrix of the material, and finally through the rubber vulcanization of resin curing, the fibers and fillers are bonded. Combined together, it forms a friction plate product with a dense texture, considerable strength and can meet the performance requirements of friction materials. The quality requirements for the resin are:
(1) Good heat resistance, good thermal decomposition temperature and low thermal weight loss.
(2) The fineness of the powdered resin should be high, which is conducive to the uniformity of the dispersion of the mixture and can reduce the amount of resin used in the formula.
(3) Low free powder content.
(4) Appropriate curing speed and flow distance.
2. Fiber reinforced materials
The fiber reinforced material constitutes the base material of the friction material, which endows the friction product with sufficient mechanical strength, so that it can withstand the load force of the grinding and riveting process of the friction plate during the production process and the friction caused by braking and transmission during use. Impact, shear, pressure. my country's relevant standards and automobile manufacturers put forward corresponding mechanical strength requirements for the friction plate according to the actual working conditions of the friction plate. Such as: impact strength, flexural strength, compressive strength, shear strength, etc. In order to meet these strong performance requirements, it is necessary to select appropriate fiber varieties to increase and meet the strength performance.
Friction material requirements for its fiber components:
(1) The enhancement effect is good.
(2) Good heat resistance. Fusing, carbonization and thermal decomposition will not occur at the friction working temperature.
(3) Has a basic coefficient of friction.
(4) The hardness should not be too high to avoid brake noise and damage to the brake disc or drum.
(5) The process has good operability.
3. Filling
The filler in the friction material component is mainly composed of friction performance regulator and compounding agent. The purpose of using fillers mainly includes the following aspects:
(1) Adjust and improve the friction performance, physical properties and mechanical strength of the product.
(2) Control the coefficient of thermal expansion, thermal conductivity, and shrinkage of the product to increase the stability of the product size.
(3) Improve the brake noise of the product.
(4) Improve the manufacturing process performance and processing performance of the product.
(5) Improve the appearance quality and density of the product.
(6) Reduce production costs.
