逆相变退火中锰钢裂纹启裂行为

摘要：采用单轴拉伸及原位拉伸对逆相变退火中锰钢（0.13C-5Mn）进行拉伸实验，用XRD、EBSD、SEM及纳米硬度等方法表征了实验钢拉伸前后组织演变规律，研究了拉伸过程中裂纹启裂行为。结果表明，中锰钢在单轴拉伸过程中微孔萌生以铁素体/马氏体界面为主，夹杂物、铁素体和新鲜马氏体内部也成为裂纹萌生的重要位置，裂纹扩展不同路径造成单轴拉伸断口呈既有韧窝区域，又有解理和准解理区域的混合特征。

Crack initiation of ART annealed medium manganese steel

The crack initiation in ART-annealed medium manganese steel (0.13C-5Mn) was studied by uniaxial tensile and in-situ tensile test, and the microstructure evolutions of the test steel before and after tension were characterized by XRD, EBSD, SEM and nano hardness. The crack initiation behavior during the tensile process was studied. The results show that the crack nucleation is occurred mainly on the interface between ferrite/martensite during uniaxial tensile process, and other positions such as inclusions, the interior of ferrite and the fresh Martensite also are important positions of crack initiation. The different crack propagation paths result in the mixed characteristics of dimple area, cleavage and quasi-cleavage area.