Abstract: The Φ80 mm rolled product of high quality gear steel 20MnCr5H-l for car (/% ： 0.17-0.22C, ≤ 0.12Si, 1.0~1.5Mn, ≤ 0.035P, 0.015-0.035S, 0.8-1.3Cr, ≤ 0.0020O, 0.015-0.045A1) has been developed by 40 t EAF- LF- VD- 3.7 t ingot casting-rolling process. With the process measures including controlling EAF end [P] W 0. 015% , LF refining slag basicity ≥ 2.5 and adjusting content of elements in steel, VD treating and feeding sulphur wire, the analysis of 5 heats steel 20MnCr5H-l is (/%：) 0.16-0.20C, 0.05-0.12Si, 1.20-1.30Mn, 0.009-0. 025P, 0.020-0.035S, 1.00-1.10Cr, 0.0008-0.0015O , 0.015-0.040Al, hardenability band width △HRC 4, and each index all meets the requirement.

Key words: Gear Steel 20MnCr5H-1, 40 t-EAF-LF-VD-3.7 t Ingot Casting Process, Hardenability Band, Oxygen Content

摘要： 采用40 t电弧炉-LF-VD-3.7 t锭模铸-轧制工艺开发了20MnCr5H-1高品质齿轮钢(/%:0.17~0.22C，≤0.12Si，1.0~1.5Mn，≤0.035P，0.015~0.035S，0.8~1.3Cr，≤0.0020O，0.015~0.045A1)-Φ80 mm材。通过控制EAF终点[P]≤0.015%,LF精炼渣碱度≥2.5，并调整钢中元素含量，VD处理、喂硫线等工艺措施，试制的5炉20MnCr5H-1钢的成分为(/%):0.16~0.20C，0.05~0.12Si，1.20~1.30Mn，0.009~0.025P，0.020~0.035S，1.00~1.10Cr，0.0008~0.0015O，0.015~0.040Al，淬透性带宽△HRC为4，各项指标均满足要求。

关键词: 20MnCr5H-1齿轮钢, 40 t EAF-LF-VD-3.7 t铸锭工艺, 淬透性带, 氧含量