Experimental Study On Surface Laser Quenching Parameters Of CL60 Wheelssteel

The abrasive wear between locomotive wheels and railway tracks is a long-standing issue in China.This issue is quite prominent in China Railways' high-speed and heavy load development.Laser-quenching is a kind of advanced surface hardening technology which can be used to improve materials' surface hardness and abrasive wear resistance and the main factors affecting the quenching effect are the various technological parameters of the quenching process.This paper takes C.L60 wheel steel as the research object,in order to obtain the best quenching effect,studies the influence law of various process parameters on its quenching performance,and obtains the optimum quenching parameters.which is mainly divided into the following contents:The first step is to study the quenching temperature field under different power by ANSYS(a finite element simulation software)and to make laser-quenching experiments under the same power parameters.Combined with the results of simulation and experiment,and with the analysis of the laser power effect on the properties of CL60 quenching rule through the factors of quenching morphology,micro-hardness,micro-structure,the optimum power parameters are carried out.Based on the optimum powerparameters,the simulation and experiment under different laser scanning rates are carried out,and by the same method,the influence of scanning rates on quenching performance is analyzed,and the optimum rate parameters are obtained.Second step is to get the complete hardening layer.Based on the obtained optimum power and scanning speed parameters in the first step,the multichannel lap laser-quenching experiment is made.In this experiment,acomplete hardening layers made in different lap rates.By the analysis of the different lap rate tempering softening zone of the quench hardening layer(with the factors of hardening layer bottom flatness,lap zone micro-structures,micro-hardness),the optimum lap rate is got to produce the best quench hardening layer.The last step,the dry friction and abrasive wear experiments of quenched and non-quenched samples are carried out on the pin-disk friction and abrasive wear tester.The influence of the laser-quenching process on the abrasive wear resistance is tested by analyzing the friction coefficient,abrasive wear rate,abrasive wear morphology and other factors.This paper systematically studies the CL60 steel wheel laser-quenching process of various process parameters on the properties of the quenching effect,obtains the optimum quenching parameters under this experimental condition,and the parameter is verified through the friction and abrasive wear experiment of quenching process on its abrasive wear resistance.It's a guidance to solve the issues caused by the abrasive wear of wheel failure,at the same time,it has a great referential significance to the application of laser-quenching technology.