摘要
采用温轧加等温热处理工艺制备纳米贝氏体钢,研究了形变温度对纳米贝氏体相变速率的影响。结果表明,形变过冷奥氏体在503 K的贝氏体等温转变时间由常规等温淬火的50 h缩短至20 h,纳米贝氏体钢的抗拉强度为2127 MPa、延伸率为4%。在实验温度范围内进行的过冷奥氏体形变均能促进纳米贝氏体相变,相变速率随着形变温度的降低而提高。过冷奥氏体形变量大于30%后残余奥氏体组织明显细化,块状残余奥氏体全部转变为薄膜状。温轧工艺可在不恶化其它力学性能的前提下加速低温贝氏体相变,从而缩短热处理时间使生产成本降低。
Nanostructured bainite steel with an ultimate tensile strength of 2127 MPa, elongation of4% has been obtained by warm rolling followed with isothermal heat treatment.The effect of deformation temperature on transformation of nano bainites has been investigated. The results show that with a proper warm defromation, the time required for the transformation of the supercooled austenite into bainite can be shortened from 50 h to 20 h. The deformation rates of supercooled austenite adopted at all temperatures in the experiments can accelerate the low temperature nanobainite transformation, while the transformation rate increased with the decreasing deformation temperature. With a deformation rate above 30%, the retained austenites were sharply refined and the blocky austenites were diminished. The low temperature nano bainite transformation can be accelerated by warm rolling process without harm to the strength, thus shortening the time of heat treatment resulting in cost saving of the steel production.
出处
《材料研究学报》
EI
CAS
CSCD
北大核心
2015年第3期207-212,共6页
Chinese Journal of Materials Research
基金
国家自然科学基金51271035和51371032资助项目~~
关键词
金属材料
纳米贝氏体
温轧
相变动力学
组织结构
力学性能
metallic materials,nanobainite,warm rolling,transformation kinetic,microstructure,mechanical properties
