Temperature dependent interfacial microstructure in HIP-bonded Al6061/Zr joints

Aluminum alloy 6061 (Al6061) was bonded to Zr foil by hot isostatic pressing (HIP) at 450°C and 560°C under 103 MPa for 90 min to investigate interfacial microstructure and bond strength. Sound metallurgical bonding was achieved under both conditions. An (Al,Si)₃Zr intermetallic layer formed at the interface, with its thickness increasing from approximately 100 nm at 450°C to about 2100 nm at 560°C, reflecting enhanced interdiffusion at elevated temperature. Peel testing revealed nearly a twofold increase in interfacial strength at the higher temperature, highlighting the influence of elevated processing temperature on diffusion kinetics and interfacial bonding. These results provide insight into diffusion-controlled phase formation and interface optimization in HIP-boned Al/Zr systems, with implications for advanced structural and nuclear applications.