Slurry Sprayed Mullite Coatings and Their Corrosion Performances

Background

Over the past three decades, many fabricating methods have been developed for depositing ceramics and other coating materials on a metal substrate. All these fabricating techniques can be categorized into three main groups: deposition techniques, flame spray techniques, and bulk processes (Kieback et al, 2003). Each fabrication method differs from each other considerably, in the context of physical principal utilized, cost, and intricacy. However, the main hindrance in the pervasive utilization of these techniques is the sophisticated equipment and thus manufacturing cost involved. Besides, most of these already established fabrication methods have not been effective in large curved areas. Despite, the existence of pre-established and consolidated deposition techniques, an active research fraternity strives for novel and cost-effective alternatives, both for the method and feedstock materials. Moreover, the use of low fabrication cost stages and the possibility to utilize the industrial waste makes it easy to imagine the potential material and cost saving offered by SST. Slurry spray technique (SST) is conceived to be as an analogous to the thermal spray coating regime, because of the use of thermal energy required for sintering of the powder constituents. SST being relatively facile and unutilized deposition technique requires supplementary research efforts for it to make commercially viable.