Mechanical and Physical Properties of Al2O3-TiAl deposited by Thermal Spraying Method

Abstract

In the current article, some physical properties of a system based on alumina (Al₂O₃) and supported by various weight ratios of TiAl were studied (5, 10, 15, 20, 25wt.%) by means of thermal spraying by flame, where oxygen gas was used at a pressure of 4bar, and acetylene at 0.7 bar. The base used for the coating is stainless steel type 316L, and a primary binder of 80%A1-20%Ni was coated with a thickness of approximately 100µm, while the base coating was 300µm thick, so that the total thickness was 400µm. The heat treatment of the final paint was carried out at a temperature of 1000°C for an hour and a half, after that physical tests were carried out through which the best mixing ratio was obtained, with a constant spraying distance of 16cm, and a constant spraying angle of 90° if found at that. The ideal conditions and after sintering that the best micro hardness is 56kg/mm², the least porosity is 9.1%, and the highest adhesion strength is 29, while the results of the scanning electron microscope showed that the best mixing ratio is the 25wt.% in which the surface was homogeneous and has a consistent composition. An indication of the improvement of the samples with the continuation of repeated additions of the support material (TiAl).