ENHANCEMENT OF THE WEAR RESISTANCE FOR C70275 CU- NI ALLOY BY LASER TREATMENT

The effect of LSP technique to enhance wear resistance of C70275 Cu - Ni alloy was investigated. In this work, C70275 Cu alloy was hardened by using Nd: YAG laser (λ=1064 nm, t=10 ns). Four different laser number of pulses and energies have been used to perform hardening (40, 60, 80, and 100) (100, 300, 500 and 700mJ) respectively. A pin-on-disc technique was used to evaluate wear rate of the specimens untreated and specimens treated by Nd: YAG laser at different applied loads and with 750 r.p.m and 60.8 HRC of rotating disc. The findingsexplain that the wear rate increases with increasing applied load, wear rate for laser energy 700mJ less than another used energies. Also the wear rate for number of pulses 100 less than another used number of pulses, and the maximum value of micro-hardness for laser energy and number of pulses(700mJ and 100 pulses)in a row,  more than another energies and number of pulses..