Abstract:
This work examines how friction coefficient is affected by amplitude and frequency of
vibration at different directions of vibration. Variation of friction coefficient with the
amplitude and frequency of vibration and induced jerk is experimentally investigated at
different directions of vibration. This is done by sliding a mild steel pin on different
types of material such as. glass fiber reinforced plastic (GFRP). ebonite.
polytetrafluoroethylene (PTFE). rubber and mild steel. A pin-on-disc apparatus having
the facility of vibrating the test samples is designed and fabricated to give different
directions. amplitudes and frequencies of vibration. The directions of vibration are both
vertical and horizontal. Horizontal vibration is created along and perpendicular to the
direction of sliding velocity. The effects of sliding velocity. duration of rubbing.
roughness. normal load. relative humidity and lubrication on friction are investigated in
this research work.
Studies have shown that the value of friction coefficient depends on the amplitude.
frequency and direction of vibration. It is observed that friction coefficient decreases
with the increase of amplitude and frequency of vibration when the direction of
vibration is vertical. On the other hand friction coefficient increases with the increase of
amplitude and frequency of vibration when the direction of vibration is horizontal. The
horizontal vibration can be of two types. one in the longitudinal direction. and othe,r in
the transverse direction. Magnitude of friction coefficient for longitudinal vibration is
less than the magnitude obtained under transverse vibration.
Experiments are carried out for frequency of vibration from 0 to 500 Hz and amplitude
of vibration from 0 to 200 microns. In this study. it is also observed that the percentage
variation of friction coefficient has a particular relationship on the amplitude, frequency
and direction of vibration. The experimental results are compared with those available
in the literature.
