Effect of argon ion bombardment on diffusion bonding of SUS304L stainless steel and pure iron

The surfaces of SUS304L stainless steel and pure iron specimens prepared by a lapping method were treated with argon ion bombardment, and then diffusion bonding was carried out. The effect of argon ion bombardment treatment on the properties of diffusion bonding joint was investigated by the tensile tests of joints and microstructure analyses of the fractured surfaces. The results showed that the argon ion bombardment treatment before bonding was effective to clean the bonding surface and reduce the inclusions at the bonded interface, so that the tensile strength of the bonded joints was improved and bonding temperature was lowered. The joint properties of pure iron were more excellent than those of SUS304L stainless steel. The amount of the inclusions at the joints with argon ion bombardment treatment depended on affinity of oxygen to metal.