Influence of the aluminium content of plain steels on heat treatments

The main purpose of this article is to determine the optimal level of alumi num content in plain steels to have the optimal mechanical properties by me ans of surface heat treatments. Various plain steels with different alumini um content have been studied. The importance of treatment temperature is an alyzed. The influence of other factors, like nitrogen content or the homoge neous distribution of particles, is evaluated. It is concluded that the alu minum composition of plain steels that are subjected to heat treatments sho uld not exceed 0.02 %.