Journal of the Korean Society of Manufacturing Process Engineers (한국기계가공학회지)

The Korean Society of Manufacturing Process Engineers (한국기계가공학회)
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Effect of Repair Width on Mechanical Properties of 630 Stainless Steel Repaired by Direct Energy Deposition Process

직접 에너지 적층 공정을 이용한 보수 공정에서 보수 폭에 따른 기계적 특성 관찰

  • Oh, Wook-Jin (Dep. of Ocean Advanced Materials Convergence Eng., Korea Maritime and Ocean Univ.) ;
  • Shin, Gwang-Yong (Smart Manufacturing Process Group, Korea Inst. of Industrial Technology(KITECH)) ;
  • Son, Yong (Digital Manufacturing Process Group, Korea Inst. of Industrial Technology(KITECH)) ;
  • Shim, Do-Sik (Dep. of Ocean Advanced Materials Convergence Eng., Korea Maritime and Ocean Univ.)
  • 오욱진 (한국해양대학교 해양신소재융합공학과) ;
  • 신광용 (한국생산기술연구원 스마트가공공정그룹) ;
  • 손용 (한국생산기술연구원 디지털제조공정그룹) ;
  • 심도식 (한국해양대학교 해양신소재융합공학과)
  • Received : 2019.12.02
  • Accepted : 2020.01.07
  • Published : 2020.03.31
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Abstract

This study explores the effects of repair width on the deposition characteristics and mechanical properties of stainless steel samples repaired using direct energy deposition (DED). In the DED repair process, defects such as pores and cracks can occur at the interface between the substrate and deposited material. In this study, we changed the width of the pre-machined zone for repair in order to prevent cracks from occurring at the inclined surface. As a result of the experiment, cracks of 10-40 ㎛ in length were formed along the inclined slope regardless of the repair width. Yield and tensile strength decreased slightly as the repair width increased, but the total and uniform elongation increased. This is due to the orientation of the crack. For specimens with a repair width of 20 mm, yield and tensile strength were 883 MPa and 1135 MPa, respectively. Total and uniform elongations were 14.3% and 8.2%, respectively. During observation of the fracture specimens, we noted that the fracture of the specimen with an 8 mm repair width occurred along the slope, whereas specimens with 14 mm and 20 mm repair depths fractured at the middle of the repaired region. In conclusion, we found that tensile properties were dependent upon the repair width and the inclination of the crack occurred at the interface.

Keywords

Acknowledgement

본 연구는 한국생산기술연구원 기술용역과 부산 산학융합지구조성사업단 산학협력 R&D과제의 지원을 통해 수행되었으며, 이에 감사드립니다.

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