回火工艺参数对DP600热轧双相钢组织和性能的影响

采用低温回火实验模拟热轧双相钢实际生产过程中卷取后的冷却过程，分析回火温度与保温时间对0．09C-0．1Si-1．3Mn-0．5Cr-0．05P热轧双相钢组织及力学性能的影响。结果表明，回火过程中主要是碳原子通过扩散影响铁素体与马氏体中的微结构，从而对其组织和力学性能产生影响；200℃回火后双相钢基本保持原有的组织与性能，230℃以上随回火温度升高和保温时间延长，马氏体分解逐渐明显，铁素体中碳原子钉扎可动位错造成屈服现象的发生；在230～250℃温度范围回火时，保温时间的延长较温升对回火程度的影响更加明显。

Effect of tempering parameters on the microstructure and mechanical properties of 600MPa hot-rolled DP steel

Tempering experiment was carried out to simulate the cooling process of hot-rolled DP steel in actual production, and the effects of tempering temperature and holding time on the microstructure and mechanical properties of hot-rolled DP steel with the composition of 0.09C-0.1Si-1.3Mn-0.5Cr- 0.05P were analyzed. The results show that during the tempering process, the diffusion of carbon atoms affects the microstructure of ferrite and martensite, and then influences the mechanical properties of DP steel. Tested steel almost keeps its original characteristics at 200 ℃. More martensite decomposes with the increase in tempering temperature and holding time, and the returning of the yield phenomenon is caused by the decrease in mobile dislocations which are locked by interstitial atoms in ferrite. When the tempering temperature is in the range of 230～250℃, the effect of holding time is stronger than that of tempering temperature.