This paper describes the effect of laser surface treatment on wearesistance of steel
Ck45 .A Pulse Nd:YAG laser with wave length 1064 nm and pulse duration 100 ns
was used by applying one pulse ,two pulses with different laser energies (500, 750,
1000 mJ). Pin-on-disc technique was done to define wear rate with different forces
(5, 10, 15, 20, 25 N) and different sliding speeds (1.319 ,2.199, 3.078, 3.958 m/s) for
constant time (20 min) and constant rotating disc 720 r.p.m with 45HRC .Also
defined microhardness which decreases far from the hardened surface , depth of
hardening was evaluated through optical microscopy . The results of this work
demonstrated that improvement in wear resistance for 1000 mJ laser energy more
than the other energies for one pulse and two pulses ,while wear resistance for two
pulses more than one pulse for all the energies . X-ray analysis results show that
precipitation of another carbides like iron carbides ,chromium carbides ,manganese
carbides after the treatment by laser.