The presence of an iron oxide layer at the enamel/steel interface in one-coat porcelain enamelling

Influence of preoxidation cycle on the bond strength of CoCrMoSi–porcelain dental composites

“…Posterior studies performed by Miyagawa [16] and Ritchie et al [17] have shown that a discrete oxide layer must be present at the interface. Therefore, Mackert et al [9] tried to ascertain whether the oxides formed on dental PFM alloys were sufficiently adherent to their alloys to allow for excellent porcelain adherence and concluded that adherence between oxide formed on the metal surface and porcelain plays a dominant role in porcelain.…”

Microalloy Precipitation at the Glass–Steel Interface Enabling Adherence of Porcelain Enamel

“…The formation of an oxide layer and its subsequent dissolution (at least partially) has been proposed earlier, while the formation of an ferrous ion‐saturated enamel glass as a prerequisite of a microalloy precipitation has not been reported before. In particular and this is the most striking effect, we found that these alloy particles coalesce and later bond to the steel surface.…”

Bubble Structures, Fishscaling Resistance and Adhesion of Vitreous Enamel to Low Carbon Steel

“…The hydrogen dissolves in the austenite matrix and then expelled from the steel during cooling process when the steel undergoes a phase transformation from austenite to ferrite, causing lower solubility for hydrogen in steel. Subsequent accumulation of this evolved or trapped hydrogen at interface causes crack and split of the enamel [7]. The hydrogen is mainly from the reaction product of iron and carbon in steel with water steam in the frit by the following oxidation reactions at temperature higher than 540 ºC [8]:…”