LAUSR

The quest for vehicle safety improvement with weight reduction and consequently lower fuel consumption led the automotive industry to begin research into the third generation of advanced high-strength steels. These steels present complex microstructures, composed of martensite, bainite and stable retained austenite. Two of the main treatments for obtaining these microstructures are the low-temperature austempering and quenching and partitioning (Q&P). The objective of this work is to evaluate the microhardness and adhesive wear performance of C-Si-Mn and C-Si-Mn-Nb steels submitted to the treatments mentioned above. Both austempering and the partitioning steps were conducted at Ms+50 °C. Treatment times were 1 and 3 h for austempering and 10, 30 and 60 min for Q&P. Results show that niobium addition promotes improvement in wear performance despite inferior levels of austenite stabilization and changes in the bainite morphology.