Wear behaviour of plasma-sprayed AlSi/B4C composite coatings

This paper describes the wear behaviour of AlSi/B4C composite coatings with 0–25 wt% B4C particles for diesel engine motors. These coatings were successfully fabricated on AlSi substrates using an atmospheric plasma spray technique. The produced samples were characterized by means of an optical microscope, scanning electron microscope and microhardness tester. The obtained results pointed out that an increase of B4C particles in AlSi coatings was caused on the rising of the microhardness values and the decrease of the thermal expansion coefficient of the coatings. The friction and wear experiments were performed under dry conditions using a ball-on-dics configuration against WC/Co counter material for different loads. It was concluded that wear resistance of the coatings produced using B4C powders is greatly improved compared with the substrate material. The highest wear resistance of the coatings were also determined in the 20% B4C coating.