Abstract

This study analyzes the microstructural stability of nickel aluminide coatings processed by PTA using a mixture of elemental powders (nickel, aluminium, chromium carbide and iron boride), varying the aluminum content. Deposition on AISI316L steel plates was carried out with current of 130A. The stability was evaluated using isothermal exposure at temperatures up to 1000 °C for intervals up to 72h in an air furnace. Scanning electron microscopy analysis showed precipitations of Cr-rich phases, which did not alter significantly the as-deposited hardness.