对断裂阻力曲线测量方法中钝化线的探讨

摘要

裂纹尖端钝化线的定义对于延性金属材料断裂韧性测量有重要影响,从裂纹尖端应力场的力学模型出发分析了钝化线的来源,比较了目前较为通用的测量标准E1820和GB21143-2007对于钝化线的定义,最后结合实例评价了这两种测量方法中钝化线定义的合理性。%Since the construction line defining the initial crack extension will cause significant effect on fracture toughness measurement for ductile metals, the background of the construction line was analyzed based on mechanical model of crack-tip stress field. The popular used British standard E1820-08a and Chinese standard GB21143-2007 were compared for their different definition of the construction line in test method. Finally the rea-sonability of these two kinds of construction lines was discussed coupling with test result application.