Study and Application of T22 Iron Based Powder Metallurgy Friction Materials

The development of heavy duty machines has put higher technical demand for friction materials. Iron base sintered metal friction materials is a multi-phases composite which is composed of friction component and lubricant component, and iron is used as its matrix. This material is suitable for making brake shoes of heavy duty machines and it is cheaper. We described the composition and properties of T22 iron base sintered materials for making brake shoes in armoured tracked vehicles that were developed at our laboratory. The results of comparison tests between this kind of brake shoes and casting iron shoes shown that the former not only has obviously higher heat stability and wear resistance than the latter but also has advantages of high deceleration, short break distance and long service life and can meet requirments of maneuverabi-lity and reliability of vehicles. The probation results shown that when middle-sized vehicle and light-duty used brake shoes made from T22 powder materials? their braking deceleration rose by a factor of 1.9 to 2.6 as compared with casting iron shoes) the braking distance was equated to 0.33 to 0.5 of the latter's; service life of T22 material shoes was longer 0.5 to 1.0 times than casting iron shoes'.