裂解连杆用高强度非调质易切削钢的研制

 设计了用于裂解连杆的高强度非调质易切削钢及其生产工艺，通过金相显微镜、扫描电镜等方法，分析了研制钢的显微组织、析出相及对力学性能的影响。结果表明：研制钢是由铁素体和珠光体组成，向钢中添加高的V和N元素，有利于增加更多的弥散析出相，提高其强度。轧后加速冷却，有利于铁素体晶粒细化、珠光体球团尺寸和珠光体片层间距减少、析出相增多，使其抗拉强度和屈服强度分别达到1000MPa和750MPa以上。

Development on high strengthened no-heated treatment free cutting steel used in fracture splitting connecting rod

A new high strengthened no-heated treatment free cutting steel used in fracture splitting connecting rod was studied. Microscope, SEM were used to investigate the microstructure and precipitated phase, including the connection between them and the mechanical properties. The results showed that the studied steel was made of ferrite and pearlite, when adding mass V and N to the steel it was benefit to offer a mount of precipitated phase and improve the strength. By accelerating the cooling rate after rolling it could make the ferrite thinner, pearlite group and the distance between pearlite flake smaller, precipitated phase more, whats more, it attained tensile strength and yield strength up to 1000MPa and 750MPa.