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The microstructure evolution of a eutectoid steel during the deformation induced pearlite transformation of undercooled austenite was investigated by uniaxial hot compression simulation experiment. The effects of different deformation degree, deformation rates and deformation temperature on the deformation induced pearlite transformation were explored. The results indicate that the induced pearlite transformation can occur rapidly during the deformation, for the stress accelerates phase transition. With the increase of the deformation degree, the dislocation density and phase transition driving force in the microstructure are improved, accelerating the occurrence of phase transition and the process of cementite spheroidization. For the diffusion- controlled phase transition, the deformation rates decrease to prolong the deformation time, so the carbon atoms can diffuse sufficiently to obtain spheroidized cementite. At lower deformation temperature from A1 to Ar1, significant refinement of the fragmentation of cementite occurs due to the increase of supercooling and spheroidized time. The ultrafine microstructure of cementite particles can be obtained through the high deformation degree, low deformation rates and low deformation temperature. It is also observed that the pro- eutectoid ferrite nucleates along the austenite boundary in the process of deformation. 相似文献
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分析了我国核电承压设备(反应堆压力容器、主管道、蒸发器、稳压器和安全壳等)用钢的发展现状与发展方向,并指出某些元素在核电承压设备用钢中的作用及对其辐照脆化的影响。分析认为,为了确保核电承压设备用钢的使用性能和安全性能,必须严格控制残余元素水平、组织形态等,保证锻压比和后期退火工艺参数。 相似文献
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