Interfacial behavior on Al2O3/HAYNES® 214™ joints fabricated by solid state bonding technique with Ni or Cu–Ni–Cu interlayers

The residual stresses due to the difference in thermal expansion between ceramic and metal is a significant parameter to control during the fabrication of ceramics/metal joint. In this work, residual stress distribution, after solid state bonding of different joints, was measured using X-ray diffraction (XRD) and Vickers Indentation Fracture (VIF) methods. Tensile stress concentration in alumina caused by the thermal expansion mismatch in the Al2O3/Ni/Ni alloy (HAYNES® 214™) joint severely deteriorated the assembly and caused cracks in alumina. To solve this problem, this paper shows that the use of a Cu/Ni/Cu multi-layer, associated with the direct copper bonding method (DCB), by pre-oxidation of copper, reduces significantly the tensile residual stresses in alumina material. Consequently, this process offers the possibility of producing an interlayer with a high melting temperature and hence joints which can withstand high-temperatures.