Effects of post-spraying heat treatment on wear resistance of WC-Co nanocomposite coatings

The potential of post-spraying heat treatment to improve the wear resistance of WC-Co nanocomposite coating has been investigated in the present study. Since thermally sprayed WC-Co nanocomposite coatings are much susceptible to detrimental reactions of decarburization and WC decomposition, there is certain limitation in optimization of spray parameters to improve coating performance. Heat treatment of the coatings can offer alternative solution for the promotion of wear resistance. High velocity oxyfuel sprayed WC-Co nanocomposite coating was heat-treated at a range of temperatures between 400 and 1000 degrees C, and abrasive wear resistance was then evaluated. The influence of heat treatment was discussed in terms of microstructural features and hardness of the coatings. The wear resistance of WC-Co nanocomposite coating was greatly improved by a proper heat treatment temperature. (c) 2006 Elsevier B.V. All rights reserved.