The effect of vanadium alloying on the wear resistance of pearlitic rails
Due to the increasing demand on pearlitic rails to support heavier loads and higher speeds, grooved rails for tramways and light rail transit (LRT) require strengthening via alloying or heat treatment, i.e. accelerated cooling after hot-rolling. In this study, the wear performance of five different commercial grades is compared using unlubricated twin-disc testing and detailed microstructural characterisation. Results indicate that the vanadium-alloyed steel experiences less than half the wear rate of a heat-treated grade with a similar hardness. This is attributed to the increased stability and toughness of vanadium-containing cementite, as compared to pure cementite. The evidence suggests that vanadium partitions into the cementite lamellae during the formation of pearlite. This improvement in wear resistance due to vanadium could enable an approximately two-fold reduction in the maintenance and life cycle costs relative to heat-treated rail alternatives.regarded as transition-phases relative to mixtures of cementite and ferrite.
Online Publication Date