Abstract
The effect of heat treatment on hardness and wear resistance of WC-27%NiCr sprayed coating on SUS403 made by High Velocity Oxygen Fuel Spraying (HVOF) has been studied to improve abrasive wear resistance.
Specimens were heated to either 573, 673 and 773 K and held at those temperature for various times, up to 45 h. The change in micro-vickers hardness (load 2.94 N) after heat treatment was measured after the samples coold to room temperature. The wear rate of the specimens against α-SiC with the plane-on-plane contact pressure of 0.196 MPa, in water suspending 9 mass% silica powder were measured by a sliding velocity of 0.5 m/s.
The results obtained are as follows:
(1) Heat treatment increased the hardness of WC-27%NiCr sprayed coatings.
(2) The increase of the hardness due to heat treatment was dependent on the void decreasing of the sprayed coatings.
(3) The wear rate of the heated WC-27%NiCr sprayed coatings in water suspending silica powder became triple increment against that of the coating before heating.
