The Influence of Laser Surface Hardening on Dry Sliding Wear Behaviour of Steel Ck45

Abstract

This paper describes the effect of laser surface treatment on wearesistance of steelCk45 .A Pulse Nd:YAG laser with wave length 1064 nm and pulse duration 100 nswas 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) forconstant time (20 min) and constant rotating disc 720 r.p.m with 45HRC .Alsodefined microhardness which decreases far from the hardened surface , depth ofhardening was evaluated through optical microscopy . The results of this workdemonstrated that improvement in wear resistance for 1000 mJ laser energy morethan the other energies for one pulse and two pulses ,while wear resistance for twopulses more than one pulse for all the energies . X-ray analysis results show thatprecipitation of another carbides like iron carbides ,chromium carbides ,manganesecarbides after the treatment by laser.