Research of Improving Purity and Decreasing Oxygen in Mn-Cr Series Pinion Steel for Automobile

摘要

In order to meet the need of rapid development of the automotive industry in our country and introduce pinion steel smoothly for domestic manufacture, it's very important to improve the metallurgical quality of domestic pinion steel, especially improve the purity of melted steel and decreasing the oxygen content in steel. As we know, the oxygen content in steel and the feature of inclusion is of strong effect on fatigue life of pinion. We emphasize on improving the purity, decreasing oxygen content to decrease inclusions in steel to achieve or exceed the steel quality of advanced countries. We have achieved obvious result after several-year manufacture testing. Mn-Cr series steel is pinion steel which is introduced from Volkswagen company. They all belong to low carbon steel that are required Si <= 0.12 percent, the grain size is homogeneous and >=5 grade, both Ti and V content are <=0.01 percent, the remained Al content is 0.02-0.055 percent, and the narrow variation of hardenability (<=4HRC). Designing and implementing the steelmaking process is very difficult because of these special requirements.