A novel method for the development of a low-temperature bainitic microstructure in the surface layer of low-carbon steel

A method is proposed for the development of a low-temperature bainitic microstructure in the surface layer of low-carbon steel that is based on carburization and succedent low-temperature austempering. The surface hardness can reach similar to 620 HV, and a compression residual stress of similar to 196 MPa can be produced in the surface layer. This type of microstructure is potentially used for the manufacture of heavy-duty gears. (c) 2008 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.