固溶和时效处理对Fe-Mn-Al-C轻质钢组织和硬度的影响

采用 X 射线衍射仪(XRD)、光学显微镜 (OM)、扫描电镜(SEM)和布氏硬度计等对固溶时效处理后Fe-Mn-Al-C轻质钢的显微组织和硬度进行表征分析。结果表明,随着固溶温度的升高,试验钢中奥氏体晶粒尺寸逐渐增大,在1050 ℃时,晶粒尺寸为50~200 μm,而随着时效温度的升高,奥氏体晶粒长大不明显,奥氏体基体中出现κ-碳化物和VC等第二相。随着时效温度的升高,试验钢中第二相的析出形貌逐渐由零星点状式到片状聚集式,再到链状形态分布在奥氏体基体内。试验钢的硬度随着固溶温度的升高和时效温度的降低,分别呈降低和增加的趋势。

Effect of solution treatment and aging on microstructure and hardness of Fe-Mn-Al-C light weight steel

Microstructure and hardness of the Fe-Mn-Al-C light weight steel after solution and aging treatment were characterized by XRD, OM, SEM and Brinell hardness tester. The results show that, with the increase of solution treatment temperature, the austenite grain size in the tested steel increases gradually, and the grain size is 50-200 μm at 1050 ℃. With the increase of aging temperature, the austenite grain growth is not obvious, and the second phases such as κ-carbide and VC appear in the austenite matrix. With the increase of aging temperature, the morphologies of the second phase in the tested steel gradually change from sporadic distribution to flake aggregation, and then to chain distribution in the austenite matrix. The hardness of the tested steel decreases and increases with the increase of solution treatment temperature and aging temperature, respectively.