According to the assumption of intrinsic relationship between ultimate strain energy density and microcrack nucleation,this work developed a fracture failure model to estimate the fracture toughness of A508-III steel ...According to the assumption of intrinsic relationship between ultimate strain energy density and microcrack nucleation,this work developed a fracture failure model to estimate the fracture toughness of A508-III steel in the ductile-to-brittle transition region.The fracture toughness and uniaxial tension tests at different temperatures were carried out to determine the relationship between nucleation parameter and ultimate strain energy density,from which the evolutions of fracture toughness of A508-III ferritic steel for different cumulative failure probabilities at different temperatures were predicted.The fracture failure model can well describe the fracture toughness distribution of A508-III steel in the ductile-to-brittle transition region.Compared with the master curve method,this model has better temperature adaptability.It is more convenient to calibrate the parameters of this model compared with the traditional Beremin model,and without complex finite element analysis.展开更多
针对无法直接获得载荷(P)-加载线位移(load line displacement,LLD)对应的塑性功导致无法直接完成基于直通型紧凑拉伸试样(front face compact tension,FFCT)试样材料断裂韧性测试的问题,该文基于迭代理念将适用于台阶型试样(load line ...针对无法直接获得载荷(P)-加载线位移(load line displacement,LLD)对应的塑性功导致无法直接完成基于直通型紧凑拉伸试样(front face compact tension,FFCT)试样材料断裂韧性测试的问题,该文基于迭代理念将适用于台阶型试样(load line compact tension,LLCT)的规则化法推广应用于FFCT试样,得到基于FFCT试样评估延性材料断裂韧性的可行方法。结合汽轮机转子钢和迭代方法,验证新方法准确性,最后将迭代方法应用于核反应堆材料A508-III钢的J阻力曲线测试中,有助于解决基于1/2FFCT试样获取断裂韧性的难题。展开更多
基金This work is financially supported by the National Natural Science Foundation of China(Grant Nos.11872320 and 12072294)the fund of Science and Technology on Reactor Fuel and Materials Laboratory.
文摘According to the assumption of intrinsic relationship between ultimate strain energy density and microcrack nucleation,this work developed a fracture failure model to estimate the fracture toughness of A508-III steel in the ductile-to-brittle transition region.The fracture toughness and uniaxial tension tests at different temperatures were carried out to determine the relationship between nucleation parameter and ultimate strain energy density,from which the evolutions of fracture toughness of A508-III ferritic steel for different cumulative failure probabilities at different temperatures were predicted.The fracture failure model can well describe the fracture toughness distribution of A508-III steel in the ductile-to-brittle transition region.Compared with the master curve method,this model has better temperature adaptability.It is more convenient to calibrate the parameters of this model compared with the traditional Beremin model,and without complex finite element analysis.
文摘针对无法直接获得载荷(P)-加载线位移(load line displacement,LLD)对应的塑性功导致无法直接完成基于直通型紧凑拉伸试样(front face compact tension,FFCT)试样材料断裂韧性测试的问题,该文基于迭代理念将适用于台阶型试样(load line compact tension,LLCT)的规则化法推广应用于FFCT试样,得到基于FFCT试样评估延性材料断裂韧性的可行方法。结合汽轮机转子钢和迭代方法,验证新方法准确性,最后将迭代方法应用于核反应堆材料A508-III钢的J阻力曲线测试中,有助于解决基于1/2FFCT试样获取断裂韧性的难题。