Mild-to-severe wear transition and transition region of oxidative wear in steels

Dry sliding tests for steels were performed in air under the test temperature at 400 degrees C and the loads of 50-250 N. The wear behavior and characteristics were focused on to explore their general characters in severe conditions. The wear behavior of various steels presented a common wear regular pattern; a mild-to-severe wear transition occurred with an increase of the load. Because oxidative wear prevailed, this was suggested to call the mild-to-severe wear transition of oxidative wear. More importantly, a transition region in the oxidative wear was found to exist and corresponded to the different-extent plastic deformation of the subsurface substrate. Through reviewing the past research, the mild-to-severe wear transition of oxidative wear was noticed to be a popular phenomenon in dry sliding wear of severe conditions, particularly elevated-temperature. This transition (region) with oxidative-wear characteristics was considered to the essence of wear failure in severe conditions, which was a physical and chemical process including oxidation, thermally softening and plastic deformation of worn surfaces and subsurfaces. And the wear characteristics in the transition region were revealed. (C) 2012 Elsevier B.V. All rights reserved.