Influence of Aluminum on the Wear Properties of High‐Carbon Metastable Austenitic Steels

Abstract

The two‐body abrasive wear properties of metastable austenitic steels (MAS) against SiC abrasive paper are investigated at different wear loads. To ensure a metastable austenitic microstructure, the alloying compositions are chosen such that the martensite start temperature of the MAS is approximately at room temperature, while the proportions of carbon, manganese, and aluminum change. The abrasion test results are compared to martensitic (40MnB5) and austenitic steel (Hadfield steel). An up to four times lower weight loss is found for the MAS compared to the Hadfield steel and up to 6.7 times lower weight loss compared to the martensitic steel. It is found that the wear resistance of the MAS increases significantly with wear load. Wear resistance of over 1300 Nm mm−3 is achieved at the highest wear load of 32 N. The wear properties of the MAS are associated with an increase in the surface hardness resulting from a mechanically induced austenite to martensite phase transformation. It is shown that the addition of aluminum to the MAS reduces the wear resistance. This is explained by an increase in stacking fault energy and the associated restriction of the mechanically induced transformation to martensite.