Influence of abrasive particles on wear mechanism and wear resistance in sliding abrasion tests at elevated temperatures

Abstract

The metal matrices (MMs) X2CrNiMo17-13-2 and NiCr20AlSi and the metal matrix composites (MMCs) of the latter MM with 30 v/o WC/W 2C or Cr 3C 2 as hard particles (HPs) were tested in sliding abrasion. The tests were carried out against flint, corundum and silicon carbide as abrasive particles (APs) at temperatures up to 900°C in argon. An increasing hardness ratio, H MM/ H AP, improves the wear resistance at room temperature. At elevated temperatures, the wear resistance of the MMs depends upon the formation of a self-protecting layer of embedded AP-fragments. The tests against flint and corundum revealed an increasing wear resistance up to a critical temperature T C and a sharp decrease above T C which is lower for corundum than for flint. MMs tested against SiC show a constant low wear resistance versus temperature. An important improvement in the wear resistance is achieved by the utilization of HPs in MMCs with a hardness ratio, H HP/ H AP, greater than 1.2.