成分偏析严重的12CrNi2MnCu铸钢冷脆转变特性研究

采用系列温度动态撕裂试验、断口分析和金相分析,并结合断裂力学研究了成分偏析严重的12CrNi2MnCu铸钢的冷脆转变特性.结果表明,本试验铸钢在试验温度范围内动态撕裂能普遍较低,但仍表现出冷脆转变特性.试验温度高于冷脆转变温度时,裂纹以沿脆化的一次晶晶界扩展为主,形成脆性的沿晶断裂;试验温度低于冷脆转变温度时,裂纹以在冷脆的晶内扩展为主,形成穿晶断裂.

Ductile-Brittle Transition of 12CrNi2MnCu Cast Steel with Severe Segregation

The ductile-brittle transition of 12CrNi2MnCu cast steel were studied by means of dynamic tear test,fracture a-atures range, the cast steel still has the ductile-brittle transition characteristic. When the test temperature is higher than the ductile-brittle transition temperature, the crack propagates in majority along the brittle primary grain boundary,and fracture mechanism is inter-granular brittle fracture. When the test temperature is lower than the ductile-brittle transition temperature, the crack propagates primarily within the grains, and the failure mechanism is trans-granular britde fracture.