Impact of laser hardening technological regimes on the amount of residual austenite in the laser exposure zone

Authors: I.I. Kuleshov, I.I. Chernatkin

Heat treatment and surface methods based on surface deformation are the most widespread methods for working surfaces hardening of cast iron components. It has been established that some methods of surface hardening are time-consuming or result in a relatively low surface hardness of the layer. Methods of plastic deformation are not widely used as a reinforcing operation for parts operating at a significant temperature loads due to potential relaxation in the hardened layer. Laser hardening as a method of surface hardening is the most appropriate due to the relatively high hardness of the obtained coating, and the process capacity. In the laser exposure area at some laser hardening regimes ledeburite mesh appears that incorporates the cells of austenite (residual austenite). The article investigates the influence of parameters of laser heat strengthening on the amount of residual austenite in the zone of laser exposure. Four kinds of grey pearlite cast iron are studied. As a result of the study, equations to determine the amount of residual austenite in the zone of laser exposure when processing cast iron parts have been obtained.

Keywords: laser hardening, melting area, cast iron, austenite, melting, design of experiment, quantitative analysis, point method, area ratio method.

UDC 621.375.826

About authors:

I.I. Kuleshov - Far East Branch of FAI "Russian Maritime Register of Shipping", Vladivostok, e-mail: kuleshov.ii@rs-class.org

I.I. Chernatkin - Admiral Nevelskoy Maritime State University, Vladivostok

Pages: 78-86

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For citation: I.I. Kuleshov, I.I. Chernatkin. Impact of laser hardening technological regimes on the amount of residual austenite in the laser exposure zone. Research Bulletin by Russian Maritime Register of Shipping. 2019, No. 54/55, pp. 78-86.