淬火配分处理对锻态Fe-0.2C-9Mn-3.5Al钢显微组织及力学行为的影响

分析了淬火配分处理对锻态Fe-0.2C-9Mn-3.5Al钢显微组织及力学行为的影响。结果表明,热处理态试验钢主要由块状δ-铁素体、马氏体和板条状残留奥氏体等多相构成;残留奥氏体的体积分数随等温淬火温度升高而增大,在310 ℃时达到峰值;310 ℃等温淬火后在400 ℃配分3 min时可以获得较优的综合力学性能,抗拉强度和断后伸长率分别为1175 MPa和21.50%,强塑积达到25.26 GPa·%;应力-应变曲线中存在着明显的“锯齿”状起伏,可能与亚稳态的残留奥氏体集中转变为马氏体有关。

Influence of quenching and partitioning treatment on microstructure and mechanical behaviors of forged Fe-0.2C-9Mn-3.5Al steel

Influence of quenching and partitioning treatment on the microstructure and mechanical behaviors of forged Fe-0. 2 C-9 Mn-3. 5 Al steel was analyzed. The results show that the multiphase microstructure of the heat-treated steel mainly consists of granular δ-ferrite,martensite and lath retained austenite. With the increase of isothermal quenching temperature,the volume fraction of retained austenite increases and reaches the maximum at 310 ℃.When partitioning at 400 ℃ for 3 min after quenching at 310 ℃,preferable comprehensive mechanical properties can be obtained. The tensile strength and elongation reach 1175 MPa and 21. 50% respectively,and the product of strength and elongation reaches 25. 26 GPa·%.In addition,there are obvious serration fluctuations in the corresponding engineering stressstrain curves,which may be related to the concentrated transformation of the metastable retained austenite to martensite.