A Study of Wear Resistance of Steels without Lubricants and their High Temperature Hardness

Abstract

In the present paper, the relations between wear resistance of steels and their high temperature hardness have investigated with the wear tests under dry condition and the measurments of high temperature hardness in a vacuum. The wear tests have been carried out under various sliding speeds.The wear resistance of steels, that is a reciprocal of steady wear rate, is found to be affected by the surface hardness attained during the abrading. Hence, there have been observed close relations between wear resistance and high temperature hardness. Especially for low carbon steel, specimen with larger size of ferrite grain shows lower wear resistance than the one with smaller size of ferrite grain within a lower range of sliding speed, but at higher speed the reverse is obtained. This relation of wear resistance is compatible with that of high temperature hardness, and it is considered that the grain boundary plays considerable roles in wear.For high carbon steel of pearlite structures, wear resistance depends also on high temperature hardness up to certain sliding speed, but at the higher speed, the wear resistance tends to be extremely high because the rubbing surface is hardened due to structural change.