A novel pin-on-disk machine for stick-slip measurements

A novel pin-on-disk machine is designed and constructed to provide the facility of vibrating the test samples at different amplitudes and frequencies of vibration in order to examine their effects on stick-slip amplitudes. The machine is equipped with control features and sensors with an integrated data acquisition system to regulate normal applied load and relative spindle speed. This machine is used as pin-on-disk type with the option of changing the sample jig and fixture. Friction stability of different types of soft and hard materials is investigated by means of variation of stick-slip amplitude with amplitude of normal vibration when mild steel pin slides on mild steel, glass fiber reinforced plastic (GFRP), polytetrafluoroethylene (PTFE), and rubber. Proper construction of the machine was validated by comparing the friction coefficients for tests performed on the machine with published results using similar machine. The results revealed that within the observed range the stick-slip amplitude depends on the material type and stick-slip amplitude decreases with the increase of amplitude of vibration. The rate of stick-slip amplitude reduction has a particular relationship with material, amplitude and frequency of vibration.