The microstructural evolution and precipitation behavior of the warm-rolled (WRed) medium Mn steels with no microalloying addition, single Nb addition and multiple Nb-Mo addition treated at 650 °C for various durations were investigated. Different from the lamellar microstructure of hot rolled medium Mn steels and the equiaxed microstructure of cold rolled medium Mn steels after intercritical annealing, the WRed samples of medium Mn steels exhibited the equiaxed and lamellar mixed microstructure, and the equiaxed microstructure ratio became larger with increasing durations. The addition of Nb or Nb-Mo can respectively increase yield strength of ~ 50 MPa or ~ 180 MPa in average and ultimate tensile strength of ~ 70 MPa or ~ 100 MPa in average without sacrificing the tensile ductility. The stability of austenite can be improved for the smaller average austenite grain size due to the addition of Nb or Nb-Mo. The addition of Mo to the Nb-bearing medium Mn steel can increase the density of nano-precipitates by reducing the mismatch degree between the matrix and precipitates and inhibit the coarsening rate of precipitates.

研究了在650°C下进行了不同时间处理的，无微合金添加，单Nb添加和多Nb-Mo添加的热轧（WRed）中锰钢的组织演变和析出行为。与临界轧制后的热轧中锰钢的层状组织和冷轧中锰钢的等轴组织不同，中锰钢的WRed样品表现出等轴和层状的混合组织，等轴组织的比例随时间的延长而增大。s。添加Nb或Nb-Mo可以分别提高平均屈服强度〜50 MPa或〜180 MPa，极限抗拉强度平均〜70 MPa或〜100 MPa，而不会影响拉伸延展性。由于添加了Nb或Nb-Mo，对于较小的平均奥氏体晶粒尺寸，可以提高奥氏体的稳定性。在含Nb的Mn钢中添加Mo，可以降低基体与析出物之间的不匹配度，抑制析​​出物的粗大化，从而提高纳米析出物的密度。