| Aim to application GH3128 nickel-based superalloys in the field of aerospace and weapons manufacturing, this study used transient liquid phase bonding technology (TLP) to bond GH3128 nickel-based superalloys using Ni71CrSi high temperature solder as a interlayer of for welding test. In this papper,on the basis of technical parameters on the mechanical properties, microstructure, Joint Mechanism and Joint Properties were studied primarily and systematically.Based on the joints at room temperature shear tests and 900℃shear tests found that in welding temperature of 1250℃for 60 min parameters, Joint's high-temperature mechanical properties and room-temperature mechanical properties were best.Through orthogonal analyses of results of intensity test results found that the welding temperature was its decisive influence factors of mechanical properties. The order of Various factors of room temperature properties is:Welding temperature﹥holding time﹥pressure welding. The order of Various factors of high temperature properties is : Welding temperature﹥pressure welding﹥holding time. By optimizing process parameters , the room temperature shear strength of specimen's joint can be reached 415.9 MPa, the high temperature shear strength of specimen's joint can be reached 210.1 MPa.Because of the aliguation of the solution elements in the stage of isothermal solidification, the centerline of joint formed a zone lacking solution elements.When welding temperature was 1250℃and holding time was 60 min, joint could finish the stage of isothermal solidification and start the stage of homogenization. The longer holding time could make homogenization better.Through the nanoindentation test of joint of specimens could that structure property of zone of isothermal solidification was good,but the structure property of the zone lacking solution elements was good.Through electronfractography could find that the zone lacking solution elements was weak link of joint.
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