Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
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Characteristics of Surface Hardening for Hot Work Tool Steel using Continuous Wave Nd:YAG Laser

연속파형 Nd:YAG 레이저를 이용한 열간금형 공구강의 표면경화 특성

  • 신호준 (조선대학교 정밀기계공학과) ;
  • 신병헌 (조선대학교 정밀기계공학과) ;
  • 유영태 (조선대학교 메카트로닉스공학과)
  • Published : 2007.04.01
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Abstract

Laser surface hardening technologies have been used to improve characteristics of wear and to enhance the fatigue resistance fur mold parts. The objective of this research work is to investigate the influence of the process parameters, such as power of laser and defocused spot position, on the characteristics of laser surface hardening for the case of SKD61 steel. CW Nd:YAG laser is selected as the heat source. The optical lens with the elliptical profile is designed to obtain a wide surface hardening area with a uniform hardness. From the results of the experiments, it has been shown that the maximum average hardness is approximatly 780 Hv when the power, focal position and the travel of laser are 1,095 W, 0mm and 0.3 m/min, respectively. In samples treated with lower scanning speeds, some small carbide particles appear in the interdendritic regions. This region contains fine martensite and carbide in proportions which depend on the local thermal cycle.

Keywords

References

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