Tribo-electrification mechanisms for self-mated carbon steels in dry severe wear process

The tribo-electrification mechanisms and wear behavior are investigated for self-mated metal pairs of iron and carbon steels (0.2% C, 0.45% C, 0.7% C) under the dry severe wear condition in the reciprocating friction tester. Results show that with increasing the carbon percentage of the steels, the formation mechanism of the wear particle varies from the macro-asperity removal of the slip-tongue to the micro-asperity removal of the wedge. Meanwhile, the variation of tribo-electrification with the sliding time appears to be more serious. The polarity of tribo-electrification is significantly influenced by the difference between the wear losses of the plate and pin specimens. This means the tribo-electrification is mainly caused by the effect of the material transfer for self-mated carbon steels. Under the higher surface hardness, the mean amplitude of the friction coefficient is decreased and the mean amplitude of tribo-electrification is increased. Results also show that the mean amplitude of tribo-electrification for self-mated carbon steels is linearly proportional to the electric resistivity and the relative wear rate, but inversely to the dynamic real contact area.