Transient High Heat Load Performance of Atmospheric Plasma Sprayed Tungsten Coating

Tungsten coatings on oxygen-free copper substrates were fabricated by atmospheric plasma spraying (APS) technique. The properties of the microstructure, porosity, microhardness and oxidation of the coatings were characterized and measured. In order to evaluate the thermal properties of the APS-W coating, a high current pulsed electron beam facility was introduced to carry out the transient high heat load tests. Three power densities of 0.2, 0.5 and 1.0 GW/m2 and total pulse duration of 5 ms were performed on the coating surfaces. The surface temperature and behavior of the APS-W coatings under the transient high heat load were investigated. Obvious melting and re-solidification were found on the treated APS-W coatings, and cracks were also observed on coating surface.