Adhesive wear resistance of low temperature austempered and quenched & partitioned niobium alloyed steels

The quest for safety improvement, weight reduction of vehicles 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 and abrasive wear performance of a high silicon steel with niobium and molybdenum additions submitted to the treatments mentioned above. The austempering treatment was conducted at 340 °C for 1, 3 and 5 hours. Partitioning steps in Q&P were performed at 250 °C for 10, 30 and 60 minutes. Results show that long duration austempering treatments (3 and 5 hours) yielded better wear resistance compared to all Q&P treatments.