回火温度对贝氏体耐磨钢组织和性能的影响

对贝氏体耐磨钢进行控轧控冷+回火工艺，探究不同温度回火后贝氏体耐磨钢的组织演变和性能。结果表明，经控轧控冷工艺和200℃回火后，试验钢获得较为理想的无碳化物贝氏体/马氏体复相组织，组织中包含8.7%(体积分数)的残留奥氏体。该工艺下钢板获得较好的强韧性匹配，屈服强度达到1172 MPa,抗拉强度达到1613 MPa,断后伸长率达到19.4%,-20℃冲击吸收能量为47 J,并可满足NM500级别的硬度要求。520℃回火后大量粗大碳化物析出，且残留奥氏体基本分解完毕，导致钢板强韧性下降。

Effect of tempering temperature on microstructure and properties of bainitic wear-resistant steel

Microstructure evolution and properties of bainitic wear-resistant steel produced by thermo-mechanical control process (TMCP) + tempering at different temperatures were studied. The results show that after TMCP and tempering at 200 ℃, an ideal carbide-free bainite/martensite complex structure is obtained, which contains 8.7vol% retained austenite. The optimal combination of strength and toughness is obtained under this process. The yield strength and tensile strength reach 1172 MPa and 1613 MPa, the elongation after fracture reaches 19.4%, and the impact absorbed energy at -20 ℃ is 47 J, and the hardness can meet the performance requirements of NM500 level. After tempering at 520 ℃, a large number of coarse carbides precipitate, and retained austenite almost decomposes completely, resulting in the decrease of strength and toughness of the steel.