Effect of bonding time on microstructure and mechanical properties during TLP bonding of nickel-base superalloys Hastelloy C276 and Stainless Steel AISI316

Joining of Hastelloy C276 nickel-base superalloy to AISI316 Stainless Steel using BNi-2 interlayer performed by transient liquid phase process (TLP) at 1150°C for 5 and 30 minutes. Bonding microstructure was studied using an Optical microscope and a scanning electron microscope (SEM). Vickers hardness test and shear strength test have been used to evaluate the mechanical properties. Microstructural studies showed that at 5 and 30 minutes of bonding time, isothermal solidification is completely formed, and the Center of the joint is free of any eutectic intermetallic compounds. Also, Findings showed that the DAZ of Hastelloy C276 nickel-base superalloy contains rich borides of Ni, Cr, Mo, and W, and the DAZ of 316 austenitic stainless steel contains borides rich in Fe, Cr, and Ni.