Interface microstructure of diffusion bonded Ni3Al intermetallic alloy and austenitic stainless steel

The diffusion bonding of a Ni3Al intermetallic alloy to an austenitic stainless steel has been carried out at temperatures 950, 1000 and 1050 °C. The influence of bonding temperature on the microstructural development and hardness across the joint region has been determined. The microvoids in the interface have been found to decrease with increasing bonding temperature. The intermetallic phase Al3Ni has been detected at the Ni3Al side of the diffusion couple. Diffusion of Cr and Fe from the stainless steel to the Ni3Al alloy has been observed.