CAJ | 학술논문

以Q235钢为母材进行手工自蔓延立焊试验，并利用接头拉伸性能测试、SEM、EDS和XRD研究焊接接头的抗拉强度及断口形貌。结果表明，手工自蔓延立焊Q235钢所得焊接接头在进行拉伸测试时，塑性变形不明显，抗拉强度可达367 MPa。断口发现大量均匀细小的等轴韧窝和一定量的撕裂棱，拉伸试样的断裂是韧性断裂与准解理断裂混合的断裂方式。分析焊接接头组织发现，获得的焊缝合金为铜铁镍合金，富铜相与富铁相均匀分布，但由于焊缝合金中富铜相和富铁相的界面结合比熔合区与热影响区界面结合差，进行拉伸试验时在焊缝合金区断裂。
이Q235강위모재진행수공자만연립한시험，병이용접두랍신성능측시、SEM、EDS화XRD연구한접접두적항랍강도급단구형모。결과표명，수공자만연립한Q235강소득한접접두재진행랍신측시시，소성변형불명현，항랍강도가체367 MPa。단구발현대량균균세소적등축인와화일정량적시렬릉，랍신시양적단렬시인성단렬여준해리단렬혼합적단렬방식。분석한접접두조직발현，획득적한봉합금위동철얼합금，부동상여부철상균균분포，단유우한봉합금중부동상화부철상적계면결합비용합구여열영향구계면결합차，진행랍신시험시재한봉합금구단렬。
The base metal of Q235 was welded by manual self-propagating high-temperature synthesis (SHS) vertical weld. Tensile strength and fracture microstructure of joints were studied by tensile testing, XRD, SEM and EDS. The results show that tensile strength of the joint is 367 MPa, but plastic deformation of joints by manual SHS vertical weld is not obvious in the tensile testing. A large amount of uniform, fine and equiaxial dimple and a small quantity of tear ridge appear in the fracture of weld alloy zone. And the fracture of tensile testing is a mix of dimple fracture and quasi-cleavage fracture. The analysis of weld microstructure indicates that weld is constituted by uniform distribution of Fe-rich phase and Cu-rich phase, which are both comprised of Cu-Fe-Ni alloy. Interfacial bonding between Fe-rich phase and Cu-rich phase in weld alloy is poorer than that between the fusion zone and the heat affected zone, and fracture occurs in the weld alloy during the tensile testing.