Abstract: In order to meet the manufacturing requirements of high reliability and high precision for radar components, the diffusion welding test is carried out for the heat-treatable aluminum alloy the 6063 aluminum alloy sample plate and the radar product-related test specimen. The surface of test specimen is cleaned before welding to remove surface impurities and oxide film. After welding, dimension inspection, sealing property test, strength test and metallographic test are carried out to evaluate the weld quality. The dimension of the reinforcing bar of the specimen is obviously deformed after welding and the deformation is proportional to the pressure. The sealing performance of the specimen meets the product requirements. The average tensile strength of the sample plate is 169.3 MPa. There are local hole defects in metallographic detection, which isrelated to insufficient diffusion time or insufficient grain boundary migration of the welded surface caused by too many interfacial inclusions. So the surface state of the welded parts and the reasonable selection of welding process parameters in the diffusion welding are very important to the quality of weld joint.