Abstract
The effect of plasma-sprayed Al2O3-TiO2 and Ni-Cr alloy coatings as undercoatings of PTFE resin on the corrosion resistance of various Al-alloy substrates was investigated by atomic absorption analysis of dissolved Al3+ ions in a solution of 1% NaCl+1% EDTA. Ni-Cr coatings promoted substrate corrosion, while those of Al2O3-TiO2 exhibited high corrosion resistance. With a coating of Al2O3-TiO2, even Al-diecasts containing less than 84wt.% Al showed corrosion resistance similar to that of alloys containing more than 96wt.% Al.
