Abrasive wear behavior of detonation sprayed WC-12Co coatings: Influence of decarburization and abrasive characteristics

摘要

The major objective of the present work is to evaluate the influence of decarburization of the WC-12Co coatings and also the abrasive characteristics on its abrasive wear behavior using a planned set of dry sand rubber wheel abrasion tests. Towards this purpose, detonation sprayed coatings have been deposited at three levels of oxygen to fuel ratios so as to obtain WC-12Co coatings with decarburization lying in the wide range of 4.4-45%. Additionally, to study the interrelationship between the abrasive characteristics and decarburization on abrasive wear, the abrasive wear tests have been conducted on WC-12Co coatings using three abrasives, i.e. SiO_2, Al_2O_3 and SiC. The results indicate that WC-12Co coatings with the decarburization levels of 4.4 and 34% results in similar abrasion rates irrespective of the type of abrasive used. However, WC-12Co coatings with a decarburization of 45% exhibited high abrasion rate and the observed increase in wear rate was also associated with a change in abrasion mechanism from one dominated by WC cuboid pullout to that of inter-splat cracking induced delamination. The wear induced subsurface damage has also been investigated.