论文部分内容阅读
以自主设计的稀土改性Si-Mn-B系贝氏体-马氏体复相耐磨钢为研究对象,利用正交试验研究了不同淬火温度、淬火保温时间、回火温度、回火时间对材料强度、冲击功的影响,以确定最佳热处理工艺,并利用XRD、OM、SEM、TEM方法对其最佳热处理工艺组织进行分析。结果表明:淬火温度对抗拉强度影响最大,回火温度对屈服强度的影响最大,淬火保温时间对冲击功的影响最大。最优热处理方案为:900℃×1.5 h油淬+300℃×3 h回火处理。按此方案热处理后有较好的强韧配合:抗拉强度为1903 MPa,屈服强度为1591 MPa,洛氏硬度为51.4 HRC,无缺口冲击功为267 J。采用彩色金相-化学腐蚀法,组织为下贝氏体(49.6%)、板条马氏体(43.9%)和少量残留奥氏体(6.5%)。
Taking the self-designed rare earth-modified bainite-martensite multi-phase wear resistant steel of Si-Mn-B series as the research object, the effects of different quenching temperature, quenching holding time, tempering temperature, tempering time On the strength of materials, impact energy, to determine the best heat treatment process, and the use of XRD, OM, SEM, TEM analysis of the best heat treatment process organization. The results show that quenching temperature has the greatest impact on tensile strength, tempering temperature has the greatest effect on yield strength, and quenching holding time has the greatest impact on impact work. The optimal heat treatment program is: 900 ℃ × 1.5 h oil quenching + 300 ℃ × 3 h tempering. According to this scheme, there is a better toughness after heat treatment: the tensile strength is 1903 MPa, the yield strength is 1591 MPa, the Rockwell hardness is 51.4 HRC, and the unnotched impact energy is 267 J. Color metallographic - chemical etching method, the organization of lower bainite (49.6%), lath martensite (43.9%) and a small amount of retained austenite (6.5%).