Wear resistance of annealed plain carbon steels in pre-strained condition

The primary aim of this investigation is to examine the influence of pre-strain on wear behaviour of plain carbon steels. Experimental work comprises of detailed measurement of wear rate, microstructural characteristics, hardness, tensile properties of unstrained and pre-strained specimens, and SEM examinations of the worn-out surfaces and subsurfaces of five hypo-eutectoid and one nearly eutectoid steel. The results assist to infer that: (1) wear rate of pre-strained specimens increases with increasing pre-strain up to a critical value of the latter beyond which it drops with further increase in pre-strain, (2) wear behaviour of all the investigated hypo-eutectoid steels exhibits a critical pre-strain as 0.7 ± 0.05, normalized with respect to uniform strain, (3) simultaneous increase of wear rate and hardness up to the critical value of pre-strain is contrary to Archardʹs law; this has been explained by the ease of nucleation of voids/micro-cracks and their subsequent propagation during sliding wear of pre-strained specimens, and (4) wear rate is found to be considerably dependent on the microstructural constituents of the steels beyond the critical value of pre-strain.