【摘要】 本文研究了高碳钢在893k 温度下超塑形变过程中组织结构的变化。尽管含碳1.2wt％的钢形变前的原始组织中存在一些片层状珠光体,但以0.31mm/min 的速度拉伸后仍获得了442％的延伸率。由于这些片层状珠光体在形变过程中迅速球化,因而对钢的超塑性能无明显妨害。在形变中,球状渗碳体发生彼此相连,含碳1.6wt％的钢中的渗碳体形成沿晶界的条状和网状,考虑到钢的室温力学性能,作者建议用于超塑成形的钢的含碳量选择在0.8～1.2wt％范围。更多还原

【Abstract】 This paper introduces a study of the microstructure of high carbon steels during superplastic deformation at the temperature of 895 K.Although the initial microstructure of 1.2 pet carbon steel contains some lamellar pearlites before deformation,its elongation tofailure is still as high as 422% at the tensile speed of 0.31mm/min.This is because these lamellar pearlitcs can be soon spheroidized during de formation and have little harm to the super- plasticity of high carbon steels.It is found that spheroidal cementites linked with each other during deformation.In 1.6 pct carbon steel,cementites became long rod-like and net-like along grain boundaries after deformation.Consider- ing these mechanical properties at ambient temperature,the author suggest that the carbon content of superplastic deformation steels be within the range of 0.8-1.2%.更多还原