Efficient Coating Method via Matching Rough Surface of Stainless Steel with Al₂O₃ Particles

An efficient method of coating alumina (Al₂O₃) on stainless steel has been investigated by matching the rough surface of the substrate with different sizes of Al₂O₃ particles. An empirical correlation was established based upon the data of a controllable and measured pore size of the substrate surface by varying etching conditions. The correlation agreed fairly well with experimental results (deviations of ±20%). The Al₂O₃ coatings prepared by powders with average particle size of 324 nm had an optimal adhesion performance, and the minimum of coating weight loss on the inner surface of tubule after ultrasonic vibration was 1.7 wt %. The developed method of Al₂O₃ coating has potential prospects for the preparation of monolithic catalyst support.