An investigation was performed to evaluate the effect of the Ti–Mo–Nb co-addition on the microstructure and the tensile behavior of a Fe–26Mn–8Al-1.5C austenitic steel after aging at temperatures from 500 to 600 °C. The co-addition of Ti–Mo–Nb in the steel refines grains, increases the sizes and volume fractions of κ-carbides, and forms inter- and intra-granular (Ti,Mo,Nb)C particles. The promotion effect of Ti–Mo–Nb on the κ-carbides precipitation varies with different aging temperature. The steel with co-addition of Ti–Mo–Nb possesses higher yield strength due to the combination of grain refinement, more κ-carbides precipitation, and the formation of fine (Ti,Mo,Nb)C particles distributed uniformly within the grains, but has lower ductility ascribed to the coarseness of κ-carbides with larger volume fraction and the existence of micron-sized inter-granular (Ti,Mo,Nb)C particles along the grain boundaries. With aging temperature increasing, the strength increases but the ductility decreases for both steels with and without microalloying. In addition, the strengthening mechanisms were analyzed quantitatively. The results show that the precipitation hardening is the dominant strengthening mechanisms for both steels.

进行了一项研究，以评估Ti-Mo-Nb共添加对Fe-26Mn-8Al-1.5C奥氏体钢在500至600°C时效后的显微组织和拉伸行为的影响。钢中Ti-Mo-Nb的共添加可细化晶粒，增加κ碳化物的尺寸和体积分数，并形成晶粒间和晶粒内（Ti，Mo，Nb）C颗粒。Ti-Mo-Nb对κ碳化物沉淀的促进作用随不同时效温度而变化。由于晶粒细化，更多的κ碳化物沉淀以及在晶粒内均匀分布的细小（Ti，Mo，Nb）C颗粒的形成，共混Ti-Mo-Nb的钢具有更高的屈服强度，但延展性较低，这归因于具有较大体积分数的κ碳化物的粗糙度以及沿晶界存在微米级晶粒间（Ti，Mo，Nb）C颗粒。随着时效温度的升高，无论有无微合金化，两种钢的强度都增加，但延展性下降。此外，定量分析了强化机理。结果表明，沉淀硬化是两种钢的主要强化机制。