摘要 |
A method for processing a low manganese steel is more cost effective and improves residual stress, bending fatigue, and surface characteristics for driveline components. The low manganese steel comprises in combination, by weight, about 0.30-0.75% carbon (C) and 0.15-0.40% manganese (Mn), with the balance being essentially iron (Fe). The method for processing the low manganese steel includes carbonitriding the low manganese steel at temperatures between 1600° F. to 1750° F. for a time period of about three to six hours. The low manganese steel is subsequently quenched in a water based solution that is kept at room temperature. The process provides the low manganese steel with an irregular case profile with a core hardness of no more than 50 Rockwell C and a surface hardness of approximately 58-63 Rockwell C. Further, the process provides the low manganese steel with little or no intergranular oxidation or surface high temperature transformation product. |