Effect of Bonding Temperature on Microstructure and Mechanical Properties of 304L/Zircaloy‐4 Diffusion‐Bonded Joints with Ni/Ta Hybrid Interlayer
Zhen Wang, Yangyang Guo, Lingbao Ren, Gaofeng Quan, Yan Liu, Houhong Pan
Abstract
Diffusion bonding of stainless steel 304 L and zircaloy‐4 (Zr‐4) in solid state is conducted using Ni and Ta as the hybrid interlayer at the bonding temperature of 850−1000 °C for the bonding time of 30 min under the bonding pressure of 6 MPa in vacuum. The effect of the bonding temperature on the microstructure and the mechanical properties of the joints is investigated. The microstructure analysis is conducted by a scanning electron microscope, energy dispersive spectroscopy, and X‐ray diffraction. The mechanical properties of the joints are measured by a shear test and microhardness test. The results show that Ni 3 Ta intermetallic compounds are formed at the Ni/Ta interface, and the solid solution of Zr and Ta appears at the Ta/Zr‐4 interface. In the meantime, the maximum shear strength reaches 194 MPa and the highest hardness value across the interface of joints is 356 HV in the Ni 3 Ta layer.