Abstract
Stainless steel is applied in a wide range of fields as a material with high heat and corrosion resistance. Welding, brazing, and solid-phase bonding are the most common joining techniques for stainless steel. Conventional joining methods have issues such as local thermal distortion of the joining area and the need for high-temperature heat treatment at 800-1000°C. In this paper, we investigated a new joining technique for stainless steel. With the aim of establishing a new joining technology for stainless steel, we joined stainless steel using the Ni Micro-Plating Bonding method (NMPB) and evaluated the shear stress and the tensile stress of the joints. The joining process is performed at about 55°C, followed by heat treatment at a relatively low temperature of 300°C or higher. Shear and tensile tests were conducted on the NMPB-joined SUS304, and the results showed that the shear stress was 114MPa and the tensile stress was 77MPa without annealing. After heat treatment at 300-400°C for 1.5h, the shear stress of 200MPa and the tensile stress of 240MPa were obtained. In addition, the heat treatment at 600-800°C for 1.5h resulted in the shear stress of 230MPa and the tensile stress of 400MPa. The plating crystallographic structure before heat treatment showed preferential orientation to <001>, but after heat treatment, recrystallization progressed beyond the boundary interface at 400°C or higher, and a non-oriented crystalline was observed.