Authors: Wanchang Sun Pei Zhang Feng Zhang Chuxu Dong Jumei Zhang Hui Cai
Publish Date: 2015/08/05
Volume: 24, Issue: 9, Pages: 3218-3227
Abstract
The influence of heat treatment from 500 to 1100 °C on the 5 wt H2SO4 solutioninduced corrosion resistance of highvelocity oxygenfuel sprayed WC17Co coatings on 42CrMo steel was investigated by using xray diffractometer XRD scanning electron microscopy SEMenergydispersive spectrometer EDS and polarization curve methods XRD analysis showed decrease in W2C phase intensity with recrystallization of amorphous Co and generation of new Co3W3C and Co6W6C phases with heat treatment Porosity distribution did not follow a particular pattern it initially increased and then decreased with increasing temperature Corrosion resistance sequence of the assprayed and heattreated coatings in 5 wt H2SO4 solution was C5 C9 CA C7 C11 Furthermore microstructure and phase structure of heattreated coatings revealed the formation of different discontinuous platelike oxide films on the surface of the heattreated coatings which indicated the vital effect of binder structure on the corrosion resistance
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