Thermo-simulation test and transmission electron microscopy (TEM) have been used to investigate the interaction between the microalloying elements Nb and Mo within the precipitates during relaxation after austenite deformation of C-Ti-Mo steel and C-Nb-Mo steel.The experimental results demonstrated that the austenitic structure was preserved both in C-Ti-Mo steel and C-Nb-Mo steel even if they were relaxed for 1000 s after deformation at 850 ℃.The strain-induced precipitate occurs in two kinds of steel.Through the energy spectrum analysis,it was found that the precipitates were Ti(C,N) and Mo-bearing Nb(C,N) respectively and there exists a strong affinity of Mo for Nb with in the precipitates.Mo atoms would enter the lattice of Nb(C,N) particles probably after Nb(C,N) formation.
