Sliding wear resistance of tempered D6ac steel

Abstract

The aim of this study was to determine the sliding wear resistance of D6ac (tempered at room temperature, 450, or 550 degrees C) and to perform tribological responds. The obtained microstructures exhibited a heavy number of misfit dislocations from work hardening of the parent material, with the degree of disorder dislocation decreasing gradually upon increasing the temperature from 450 to 550 degrees C. XRD spectra observed that the residual austenite and/or mixed structures of ferrite with the precipitation of carbides at 550 degrees C will result in a softer state than that of the room temperature specimen. The elevated temperature affected the tribological behavior and induced in the parent material a significant surface response failure. The lateral force increased gradually up to 50 mu N in the tempered cases, due to the enhanced toughness. We suggest that the increase in the coefficients of friction upon increasing the tempering temperature from 450 to 550 degrees C resulted due to a soft ferrite phase. Slightly stable fluctuations of the values of mu appeared for the surfaces scratched at a constant load; therefore, plastic deformation occurred along the wear path. For the measured results of the D6ac from room temperature to 550 degrees C, the coefficient of friction was 0.34 +/- 0.05, 0.27 +/- 0.04, and 0.13 +/- 0.02, respectively. The experimental result also can be evidenced from tribological stressing and mechanical behavior. (C) 2012 Elsevier Ltd. All rights reserved.