New Devices to Assist in Friction Material Development

Five test devices were developed to aid in the development of new friction materials.

A friction machine has been equipped with disc brake apparatus and the data compared with standard drum friction machine data.

A method has been developed which utilized fast response thermocouples to measure interface temperature distribution during dynamometer tests. Extremely high temperatures have been noted.

Three laboratory tests were developed to evaluate brake materials' susceptibility to produce noise: vibration tests to measure dynamic characteristics; friction machine tests to measure negative damping; slip-stick machine tests which use the lining's noise producing tendency to excite a resonant system.

Correlation of these tests with vehicle data were investigated and are discussed in the paper.