Investigation of the Thermal, Mechanical and Physical Properties of Elastomer-Resin Mixtures Used As Friction Materials – Effect of Ingredients

The purpose of friction brakes is to decelerate a vehicle by transforming the kinetic energy of the vehicle to heat, via friction, and dissipating that heat to the surroundings. As a part of commercial truck or automobile, brake materials have additional requirements, like resistance to corrosion, light weight, long life, low noise, stable friction; low wear rate and acceptable cost versus performance. In order to achieve the properties required of the brakes, most brake materials are not composed of single elements or compounds, but rather are composites of many materials. Even a difference of a percent or two of additive concentration can affect performance, so composition control is essential in these systems. Because of this sensitivity, in this work, mechanical, physical and morphological properties of rubber-based composite friction materials have been performed. We have studied the influence of different proportions of curing agents, phenolic resin and the effect of different rubbers on the final properties of matrices used as friction materials. We have designed our experiments by using the Taguchi method in order to reduce the number of experiments required. The mechanical and physical properties-such as tensile strength, elongation at break, hardness, swelling properties, degradation temperatures- and morphological behavior were studied. The most effective factors in variation of different properties were reported by analyzing of variance in the Taguchi method. Mechanical and physical properties of such systems were influenced predominantly by variation of resin and sulfur contents. In addition, NBR-based compounds showed higher properties than SBR-based ones.