对冷轧态、淬火态、球化态三种低合金高强钢进行了奥氏体化阶段不同加热速率(5,300℃?s－1)下的淬火-配分(Q&P)热处理,研究了加热速率对其最终显微组织和拉伸性能的影响.结果表明：在奥氏体化阶段快速(300℃?s－1)加热对冷轧态钢具有明显的晶粒细化以及加速奥氏体形成的作用,而对淬火态和球化态钢的奥氏体形成过程基本没有影响；经快速加热 Q&P 处理后,冷轧态钢的抗拉强度比慢速(5℃?s－1)加热后的提高90 MPa,伸长率仅降低0．9％,而加热速率对球化态及淬火态钢 Q&P处理后的拉伸性能影响较小；经慢速加热 Q&P 处理后,冷轧态和球化态钢中硬质相沿再结晶铁素体晶界呈条带状分布,变形时易产生孔洞.
Quenching and partitioning (Q&P)heat treatment with different heating rates (5,300 ℃??s-1 ) during austenization stage was conducted on three kinds of low-alloy high-strength steels in cold-rolled,as-quenched and as-spheroidized states,and then the effects of heating rate on the final microstructures and tensile properties of these steels were investigated.The results show that the rapid heating (300 ℃??s-1 )during the austenization stage played a role in the grain refinement and austenite formation of the cold-rolled steel,while had no effect on the austenite formation in the as-quenched and as-spheroidized steels.After Q&P treatment at the high heating rate,the tensile strength of the cold-rolled steel increased by 90 MPa comparing to that at the slow heating rate(5 ℃??s-1 ), while the elongation only decreased by 0.9%.The heating rate had little effect on the tensile properties of as-quenched and as-spheroidized steels after Q&P treatment.After Q&P treatment at the slow heating rate,the hard phase in the cold-rolled and as-spheroidized steels showed a strip-like distribution along the grain boundary of the recrystallized ferrite,resulting in the generation of holes during deformation.
参考文献
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%