Abstract: TO ADDRESS THE CHALLENGE OF VACUUM BRAZING LARGE-SIZE 6061 ALUMINUM ALLOY, THIS PAPER INVESTIGATES THE DIFFUSION BONDING OF 6061 ALUMINUM ALLOY USING A 4047 ALUMINUM ALLOY INTERLAYER IN AN ATMOSPHERIC ENVIRONMENT. THE STUDY ANALYZES THE EFFECTS OF DIFFUSION BONDING PARAMETERS ON THE MICROSTRUCTURE AND MECHANICAL PROPERTIES OF THE WELDED JOINT AND REVEALS THE MECHANISMS OF INTERFACIAL METALLURGICAL BONDING AND STRENGTHENING. THE RESULTS INDICATE THAT MG₂SI AND AL₂O₃ PHASES FORM AT THE BONDING INTERFACE, WITH THEIR SIZES DECREASING AS BONDING PRESSURE AND TEMPERATURE INCREASE. THE SHEAR STRENGTH OF THE JOINT INCREASES WITH BONDING PRESSURE, TEMPERATURE, AND HOLDING TIME, REACHING A MAXIMUM OF 62.67 MPA. THE BONDING STRENGTH OF THE JOINT IS PRIMARILY ATTRIBUTED TO THE FRAGMENTATION OF THE OXIDE FILM ON THE SAMPLE SURFACE UNDER APPLIED PRESSURE (>2 MPA) DURING WELDING, THE METALLURGICAL BONDING RESULTING FROM INTERDIFFUSION OF ELEMENTS AT THE FRAGMENTED INTERFACE, AND THE PRESENCE OF STRENGTHENING PHASES SUCH AS MG₂SI COMPOUNDS AND FRAGMENTED OXIDE FILMS AT THE INTERLAYER/BASE MATERIAL INTERFACE. THIS RESEARCH PROVIDES THEORETICAL AND TECHNICAL REFERENCES FOR THE NON-VACUUM WELDING MANUFACTURING OF LARGE-SIZE 6061 ALUMINUM ALLOY ELECTRONIC CHASSIS COMPONENTS.