PDF(Pubmed)
Abstract：
Additively manufactured a low carbon Fe-Cr-Ni-Al Corrax stainless steel has ultra-high strength, but the mechanism at work when the steel cracks is still unclear. In this study, Corrax stainless steel was tensile tested to fracture and cracks in the vicinity of the fracture surface were analyzed by scanning electron microscope and electron-backscattered diffraction. The results show that the cracks propagated at angles of 45-60° to the tensile axis. Some cracks were transgranular, and high-angle grain boundaries had little effect on crack propagation. Crack propagation was inhibited in regions with lower Taylor factors. Kernel average misorientation value analysis established that the crack propagation process is accompanied by significant plastic deformation. The influence of particles and unfused pores on crack propagation is also discussed.
摘要：
增材制造的低碳Fe-Cr-Ni-AlCorrax不锈钢具有超高强度，但是钢裂纹时的工作机理尚不清楚。在这项研究中,对Corrax不锈钢进行了拉伸断裂测试，并通过扫描电子显微镜和电子背散射衍射分析了断裂表面附近的裂纹。结果表明，裂纹与拉伸轴成45-60°的角度扩展。一些裂缝是穿晶的，大角度晶界对裂纹扩展影响不大。在泰勒因子较低的区域，裂纹扩展受到抑制。核平均取向差值分析确定裂纹扩展过程伴随着显著的塑性变形。还讨论了颗粒和未熔合孔对裂纹扩展的影响。
