自溶合金皮膜のサンドエロージョン特性と損傷機構

Abstract

Self-fluxing alloy coatings are useful for components of industrial equipments in sand erosion or wear environments as well as high temperature corrosive and oxidation environments. However, the erosion characteristics by solid particle for the self-fluxing alloys have not been adequately investigated, then needed in order to develop highly durable coating alloys and apply to practical erosive services. Erosion tests at room temperature were conducted for three types of self-fluxing alloys to obtain impact angle dependence of erosion rate or normalized erosion using a sand blast type erosion test rig. We focused on hardness, fracture toughness and fracture energy of self-fluxing alloys at room and high temperatures. The relationships between erosion characteristics and these mechanical properties were discussed and erosion rate of the self-fluxing alloys at high temperature was extrapolated. The exponent numbers which show impact angle dependence of sand erosion, and erosion rates at an impact angle of 90 degrees were well related to micro Vickers hardness and roughly related both to Brinell hardness and to fracture energy. It was found that the erosion rates for the self-fluxing alloys at high temperatures up to 873 K could be estimated as almost equal to that at room temperature, as well as equivalent mechanical properties at temperatures up to 873 K.