Effect of coating on the wear properties of stir cast Al–2Mg base short steel fiber reinforced composites

Abstract

The present investigation is on the wear behaviour of Al–2Mg base 5 wt% short steel fiber reinforced composites. The composites were prepared through stir casting. The short steel fibers were coated with copper and nickel by electroless deposition process for better fiber distribution and interface bonding to improved wear properties. Dry sliding wear behavior of cast Al–2Mg base composites has been investigated using a pin-on-disc wear-testing machine. The applied load was varied in the range of 10–40 N. The volumetric wear loss increased with increasing sliding distance and applied load. Composites with 5 wt% copper coated fibers considerably reduced the wear rate and coefficient of friction compared to matrix alloy. The wear rate increased with increasing applied load. Amongst the investigated composites, the copper-coated steel fiber reinforced composite showed maximum improvement in wear rate due to better interface bonding. The Al–2Mg base composites containing 5-wt% fibers exhibited a transition from mild to severe wear depending on sliding distance and applied load. Two modes of wear have been identified to be operative based on the detail examination of wear surface, wear debris and analysis of the wear data. The transition from mild wear to severe wear was influenced by the applied load, sliding distance, hardness and strength of the pin material adjacent to the contact surface as well as by the strain induced shear stress created by applied loads.