Delayed Failure of Plasma‐Sprayed Al₂O₃ Applied to Metallic Substrates

Abstract

Aluminum oxide coatings were applied to the ends of cylindrical metal samples of both 316L stainless steel and Ti-6Al4V ELI by a plasma spray process. These samples, fabricated into 4-point bend specimens, were used to determine both the strength and slow crack growth characteristics. The data obtained indicated that both systems were susceptible to stress corrosion. When the substrate was the titanium alloy, the delayed failure behavior was characterized by two parallel stress-corrosion reactions: one at the ceramic-metal interface and one in the coating itself. The latter became dominant at low stresses. Finally, the nature of the epoxy adhesive used to fabricate the 4-point bend samples was found to strongly influence the fatigue behavior at long failure times.

Corrosion resistance behavior of Ti/TiN multilayer coatings deposited on Ti6Al4V substrates

“…Nano multilayer ceramic/metal coatings have broad application prospects in extreme environments because of its strength, corrosion resistance and high toughness [10][11][12]. Many researchers [13,14] have found that Ti/TiN multilayer coating has better corrosion resistance and mechanical properties than monolayer TiN.…”