The effects of tempering holding time at 700°C on the morphology, mechanical properties, and behavior of nanoparticles in Ti-Mo ferritic steel with different Mo contents were analyzed using scanning electron microscopy and transmission electron microscopy. The equilibrium solid solution amounts of Mo, Ti, and C in ferritic steel at various temperatures were calculated, and changes in the sizes of nanoparticles over time at different Mo contents were analyzed. The experimental results and theoretical calculations were in good agreement with each other and showed that the size of nanoparticles in middle Mo content nano-ferrite (MNF) steel changed the least during aging. High Mo contents inhibited the maturation and growth of nanoparticles, but no obvious inhibitory effect was observed when the Mo content exceeded 0.37wt%. The tensile strength and yield strength continuously decreased with the tempering time. Analysis of the strengthening and toughening mechanisms showed that the different mechanical properties among the three different Mo content experiment steels were mainly determined by grain refinement strengthening (the difference range was 30–40 MPa) and precipitation strengthening (the difference range was 78–127 MPa). MNF steel displayed an ideal chemical ratio and the highest thermodynamic stability, whereas low Mo content nano-ferrite (LNF) steel and high Mo content nano-ferrite (HNF) steel displayed relatively similar thermodynamic stabilities.

利用扫描电子显微镜和透射电子显微镜分析了700℃下回火保温时间对不同Mo含量的Ti-Mo铁素体钢中纳米颗粒的形貌，力学性能和行为的影响。计算了不同温度下铁素体钢中Mo，Ti和C的平衡固溶量，并分析了不同Mo含量下纳米颗粒尺寸随时间的变化。实验结果与理论计算结果吻合良好，表明中含量Mo的纳米铁氧体（MNF）钢中的纳米颗粒尺寸在时效过程中变化最小。高的Mo含量抑制了纳米颗粒的成熟和生长，但是当Mo含量超过0.37wt％时，没有观察到明显的抑制作用。拉伸强度和屈服强度随着回火时间而连续降低。对强化和增韧机制的分析表明，三种不同Mo含量的实验钢之间的不同机械性能主要由晶粒细化强化（差异范围为30-40 MPa）和沉淀强化（差异范围为78-127 MPa）决定。 ）。MNF钢表现出理想的化学比和最高的热力学稳定性，而低Mo含量的纳米铁氧体（LNF）钢和高Mo含量的纳米铁氧体（HNF）表现出相对相似的热力学稳定性。对强化和增韧机理的分析表明，三种不同Mo含量的实验钢之间的不同机械性能主要由晶粒细化强化（差异范围为30-40 MPa）和沉淀强化（差异范围为78-127 MPa）决定。 ）。MNF钢表现出理想的化学比和最高的热力学稳定性，而低Mo含量的纳米铁氧体（LNF）钢和高Mo含量的纳米铁氧体（HNF）表现出相对相似的热力学稳定性。对强化和增韧机理的分析表明，三种不同Mo含量的实验钢之间的不同机械性能主要由晶粒细化强化（差异范围为30-40 MPa）和沉淀强化（差异范围为78-127 MPa）决定。 ）。MNF钢表现出理想的化学比和最高的热力学稳定性，而低Mo含量的纳米铁氧体（LNF）钢和高Mo含量的纳米铁氧体（HNF）表现出相对相似的热力学稳定性。