| 학회 | 한국재료학회 |
| 학술대회 | 2020년 가을 (11/18 ~ 11/20, 휘닉스 제주 섭지코지) |
| 권호 | 26권 1호 |
| 발표분야 | 특별심포지엄1. 최신 용접/접합기술 및 용접재료 개발 동향 심포지엄-오거나이저: 김양도(부산대) |
| 제목 | 고강도 FCA 용접금속에서 미세편석이 저온균열의 입계파괴 핵생성에 미치는 영향 |
| 초록 | The influence of preheat and microstructure on cold cracking for high strength and low hydrogen flux cored arc (FCA) weld metal was analyzed using Y-groove test. The weld microstructure showed a mixture of acicular ferrite, bainite, and predominantly martensite. Cold crack fractography identified intergranular fracture and quasi-cleavage fracture. Bainite and martensite predominated on the surface and subsurface of IF while the QCF showed inclusions that nucleated acicular ferrite. Mn and Ni segregation band exits in the intergranular region. And localized Mn and Ni segregation leads to the heterogeneity of microstructure in welds metal. Intergranular fracture is originated in the locally higher Mn and Ni segregation region because of higher volume expansion. The area of non segregation region generated the quasi-cleavage fracture because lower tensile stress is applied in the lower volume fraction of martensite. In higher Mn Segregation Region, Cold crack occurs in the higher volume fraction of martensite region because of high volume expansion. And high tensile stress leads to the intergranular fracture. Quasi-cleavage fracture is generated in the non-segregation region and resist the propagation of cold crack, when the intergranular crack propagates. |
| 저자 | 이승훈1, 박철호2, 강남현3 |
| 소속 | 1스틸솔루션, 2조선대, 3부산대 |
| 키워드 | Cold cracking; Microsegregation; Intergranular fracture; Quasi-cleavage Fracture |
