重型汽车专用非调质钢前轴工业性生产工艺

Industrial production process of unquenched steel front axle for heavy automobile

针对国内卡车前轴使用调质钢制造带来的产品力学性能下降或成本过高等缺点,自行设计一种非调质钢制造卡车前轴,使用Mn、Si等廉价合金元素代替调质钢中Cr、Ni、Mo等较贵重合金元素,所设计的空冷贝氏体钢成分定为Mn-Si-V-B系,钢号为18Mn2SiVB.通过冶炼操作研究,实验确定前轴热处理工艺,进行工业实验.经过相组织分析和疲劳强度实验对产品进行检验.结果表明,冶炼和连铸连轧条件基本满足18Mn2SiVB钢的生产设计要求.采用设计用钢18Mn2SiVB代替45号或40CrMo和40CrNiMo制造卡车前轴,从其力学性能测试结果分析,能够满足使用要求;在制造工艺上采用锻后空冷代替原有锻后调质的方法是可行的.

In view of the disadvantage of mechanical properties decrease and high cost of truck front axle caused by using quenched and tempered steel, a non-quenched and tempered steel trucks front axle was designed by using of cheap substitute, such as Mn, Si alloy elements instead of Cr, Ni, Mo and other more expensive al-loying elements. The air-cooled bainitic steel components were designed as Mn-Si-V-B steel and the No. was 18Mn2SiVB. Through smelting operations, heat treatment of front axle was determined by test and industrial ex-periment was carried out. The product was tested by phase fatigue analysis and experimental. The results show that the basic conditions of smelting and casting and rolling can meet the designed requirements of 18Mn2SiVB steel production. 18Mn2SiVB instead of 45# steel, 40CrMo or 40CrNiMo to manufacture trucks front axle can satisfy the use requirements from the mechanical test results; in the manufacturing process, using air cooling in-stead of quenched and tempered after forging is feasible.