Abstract: Widmanstatten structure is harmful which is easy to be produced in hypoeutectoid steel, 0.45%C steel for piston rod of automobile shall not have Widmanstatten structure, but the 45% C steel produced by nomal process (bloom soaking at 1120-1200 ℃，end rolling at 950 ℃) has 0.5~1.0 rating Widmanstatten structure. By increasing aluminum content from original 0.013% to 0.038% , decreasing soaking temperature to 1070-1100 ℃, decreasing end rolling temperature to 800 ℃, the Widmanstatten structure rating reduces from 0.5-1.0 to 0, which effectively prevents the formation of widnianstatten structure 0.45% C steel.

摘要： 魏氏组织为亚共析钢钢中容易产生的有害组织,汽车活塞杆用45钢要求不得有魏氏组织，正常工艺(坯1120～1200℃均热，终轧950 ℃)生产的45钢存在0.5-1.0级的魏氏组织，通过将钢中A1含量由原0.013% 提高至0.038%、坯均热温度降至1070～1100 ℃、终轧温度降至800 ℃,魏氏组织级别由0.5-1.0级降低为0级，有效防止了45钢的魏氏组织产生。

关键词: 45钢, 魏氏组织, 工艺优化