600㎫급 자동차용 석출경화형 고장력강판 Nd:YAG 레이저 용접부의 특성에 미치는 용접속도의 영향

• 영문명: Effect of the welding speed on the characteristics of Nd:YAG laser welds for automotive application: 600㎫ PH high strength steel
• 발행기관: 한국레이저가공학회
• 저자명: 한태교(Tae-Kyo Han) 정병훈(Byung-Hun Jung) 강정윤(Chung-Yun Kang)
• 간행물 정보: 『한국레이저가공학회지』한국레이저가공학회지 제10권 제3호, 25~32쪽, 전체 8쪽
• 주제분류: 공학 > 기계공학
• 파일형태: PDF
• 발행일자: 2007.10.30

영문 초록

  The effect of welding speed on the weldability, microstructures, hardness, tensile property of Nd:YAG laser welding joint in 600㎫ grade precipitation hardening high strength steel was investigated. A shielding gas was not used, and bead-on-plate welding was performed using various welding speeds at a power of 3.5㎾.
  Porosity in the joints occurred at 1.8m/min, but were not observed over the welding speed of 2.1m/min. However, spatter occurred over the welding speed of 6.6m/min. The hardness was the highest at heat affected zone(HAZ) near fusion zone(FZ), and was decreased on approaching to the base metal. The maximum hardness increased with increasing welding speed. The microstructure of FZ was composed of coarse grain boundary ferrite and bainite(upper) but the HAZ near the FZ contained bainite(Lower) and fine ferrite at a low welding speed. With increasing welding speed, ferrite at the FZ and the HAZ became finely and upper binite changed to lower bainite. In a perpendicular tensile test to the weld line, all specimens were fractured at the base metal, and the tensile strength and the yield strength of joints was equal to those of raw material. Elongation was found to be lower than that of the raw material.

목차

Abstract
1. 서론
2. 실험방법
3. 결과 및 고찰
4. 결론
참고문헌

키워드

Precipitation Hardening High Strength Steel Nd:YAG Laser Welding Speed Weldability Microstructures Hardness Tensile Property