Mechanical properties of tungsten/copper coatings produced by plasma spraying

Tungsten/copper coatings were developed using plasma spraying techniques fo r electric arc resistant. However, the mechanical properties of plasma spra yed coatings, which had an important effect on the adherent strength etc., were not clarified. Two kinds of free-standing tungsten/copper coatings, wh ich were produced by an atmospheric plasma spraying (APS) and a low pressur e plasma spraying (LPPS), were machined from the thick coatings and were us ed for experiments. The Young's modulus, Poisson's ratio and four-point ben ding strength were measured at room temperature. The experimental results s uggested that the volume fraction of tungsten or copper, porosity and oxide content had an important effect on the mechanical properties. Namely, the high Young's modulus, high Poisson's ratio and high bending strength could be obtained from the tungsten/copper coatings produced by LPPS process, bec ause of the low porosity and low oxide content.