2019 Volume 68 Issue 11 Pages 833-838
Welding of metal and polymer is attracting example of a joining technique of different materials. However, it is expected that mechanical behavior of the polymer changes markedly due to heating exceeding the melting point and residual stress. Plates of polyamide and SUS304 were welded using the hot-air welding machine under different welding conditions. The influence of heating time, distance and cooling conditions on the bonding strength of the welded structure were evaluated by tensile test. The obtained results demonstrated that the bonding strength in some specimens became larger than yielding strength of PA depending on the welding condition. However, the tensile responses considerably varied even for specimens obtained from same welding condition. The situation of fracture was classified in three cases, namely, fracture of interface, fracture of polymer, and fracture of welding area. The first and third cases were observed when the total heat given to the polymer were large and small, respectively. The strain distribution around the welding area under small deformation could be a indicator of predicting the fracture pattern of the welded specimen.
