【作者】 徐庭栋； 刘珍君； 王凯；

【Author】 Xu Tingdong;Liu Zhenjun;Wang Kai;High Temperature Materials Research Division,Central Iron & Steel Research Institute;

【机构】 钢铁研究总院高温材料研究所；

【摘要】 金属高温拉伸试验国际技术标准ISO 6892-2—2011认定,拉伸试验的拉伸温度或应变速率的改变,会引起拉伸试验测试力学性能结果的不确定性,危及拉伸试验技术的可靠性。本文描述了拉伸试验测试塑性的不确定性:中温脆性和应变速率脆性的实验现象和特征,简述了多晶金属弹性变形微观理论的基本结果,以此微观理论解释了上述两种测试不确定性的试验现象。更多还原

【Abstract】 International Standard,ISO 6892- 2,Metallic Materials—Tensile Testing:Method of Test at Elevated Temperature maintained that the strain rate variations and test temperature variations can induce the measurement uncertainty of mechanical properties in tensile testing,which will imperil the reliability of tension tests.In this paper,the measurement uncertainties of intermediate temperature embrittlement and strain rate embrittlement were first described experimentally.Second,the fundamental results on the microscopic theory of elastic deformation in metals were mentioned.Then the phenomena of the measurement uncertainties were explained based on the microscopic theory.It is shown that the elastic deformation of tension tests induces the segregation of impurities to grain boundaries and the relative embrittlement which produces the measurement uncertainties of reduction in area.更多还原