A Study on the Characteristics of Repair Welding for Mold Steel using Continuous Wave Nd:YAG Laser

연속파형 Nd:YAG 레이저를 이용한 금형강의 보수용접 특성에 관한 연구

  • 유영태 (조선대학교 메카트로닉스공학과) ;
  • 신호준 (조선대학교 레이저가공연구실)
  • Received : 2009.11.13
  • Accepted : 2010.08.05
  • Published : 2010.11.01

Abstract

In this study, wire was used as the filler material for the laser repair welding, and the phenomenon in which the supplied filler material was melted and beaded down into the specimen was examined with varying laser powers and welding speeds. The optimal processing condition was found to be the laser power of 1,300 W, the welding speed and feed wire supply speed of 0.5 ml/in and the defocused distances of +2mm. At this time, the heat input(E) was $65{\sim}75\;J/mm^2$, and no internal defect occurred. When repair welding was carried out as the optimal processing for the part that had an external defect with the radius of 2mm, the filler metal was melted, resulting in the volume smaller than the defect part and thus causing the part unfilled. Therefore, it was found to be necessary to carry out repair welding two to three times by multiple passes rather than does it only once by single pass.

Keywords

References

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