Slurry Erosion Resistance of Martenistic Stainless Steel with Plasma Sprayed Al2O3-40% TiO2 Coatings

Slurry erosion is an implicit problem in many engineering industrial components such as ore carrying pipelines, slurry pumps and extruders. In the present study, Al2O3-40% TiO2 powder particles of average particle size of 50 micrometer were deposited on EN56B martenistic stainless steel by atmospheric plasma spray technique. Ni/Cr was pre coated to work as bond coat for good adhesion between coating and the substrate material. A coating thickness of 200 micrometer was achieved. Coated and uncoated substrates were subjected to slurry erosion test as per ASTM G-119 standard. Slurry erosion test rig was used to evaluate the erosion properties at room temperature condition by varying the spindle speed. Scanning electron microphotographs were taken before and after the slurry erosion test. Microstructures reveal uniform distribution of coating materials. Eroded surface shows lip, groove, and crater formation and dense coating resulting in less porosity. Micro hardness test was evaluated and reported. EDX analysis confirms the presence of Al, Ti and O-2 particles. It was observed that, Al2O3-40% TiO2 coated substrates exhibits superior erosion resistance as compared to un-coated substrates due to higher hardness and less coating porosity. (C) 2017 Elsevier Ltd. All rights reserved.