Preparation of a modified phosphate-based adhesive and its hot bonding performance on 316L stainless steel

In this study, a novel phosphate-based adhesive was prepared by using homemade aluminum phosphate as a matrix and by adding different fillers simultaneously. The effects of calcination temperature and filler composition on the bonding mechanism and high-temperature bonding strength of the adhesive for high-temperature alloys were studied. The results indicated that the crystalline transformation of AlPO 4 occurred at 500 °C. AlPO 4 has two crystalline forms at 500 °C: orthorhombic and hexagonal. The addition of CuO to the fillers resulted in the exchange of Fe and Cu at the substrate interface and enhanced the high-temperature bonding strength of the specimens. The maximum tensile strength of the specimens reached 3.9 MPa at 500 °C. These composites have potential applications in aviation, aerospace, and other fields.