Deformation behavior and dominant abrasion micro mechanisms of tempering steel with varying carbon content under controlled scratch testing

Abstract

The objective of this paper is the investigation of the abrasive wear behavior of tempering steel by the analysis of its deformation behavior and dominant abrasion micro mechanisms under controlled single scratch testing. We analyzed single scratches induced by a sphero-conical diamond tip with constant and progressively increasing load in tempering steel with varying carbon content in the as quenched condition. Among scratch and hardness testing the analysis and characterization included the optical determination of the deformation behavior (SEM, CLSM, AFM). The results show that the deformation behavior strongly depends on applied normal load and strength (yield stress, ultimate tensile strength) as it varies with carbon content. It was shown that an increasing load leads to the transition of predominant abrasion micro mechanisms from ideal micro ploughing to wedge and chip formation. The scratch resistance increased with increasing carbon content until for higher carbon contents a saturation tendency due to the presence of retained austenite is observed. An increasing carbon content also shifted the aforementioned transition of dominant micro mechanisms not only to higher applied normal loads, but also to higher scratch depths.