Study of Slurrry Erosion Factors on Thermal Sprayed Cermet Layers

Slurry jet tests, with an impingement angle of slurry at 60degrees, were conducted on four types of materials : HP/HVOF-sprayed 73WC-20Cr-7Ni layers, arc-sprayed 56W_2C-NiCr layers, flame-sprayed and fused 4lWC-NiCrCo layers, and base metal SCS6. We examined effect of slurry wear properties on cermet layers and base metal, in regards to flow velocity, sand concentration and mean diameter of sand. It was found that volume loss rates of the cermet layers were proportional to the 2.6^<th> to 3.6^<th> power of the flow velocity, and the exponent was slightly lower than that of materials. The volume loss rates increased approximately proportionally to the first power of sand concentration and the mean diameter of sand. The slurry wear resistance increased approximately proportionally to the third power of Vickers hardness, which corresponded to results obtained on conventional cermet layers. Therefore, volume loss rates of materials can be estimated by specifying parameters, Vickers hardness, flow velocity, sand concentration and mean diameter of sand, from the results of multiple linear regression analysis