The article has been devoted to issues connected with socket fusion welding, which is next to welding one of the methods of thermoplastic polymers joining. In this paper, the research was presented, which the aim was analysis of quality of joints obtained as a result of resistance welding of polypropylene pipes with diameter ø20 in the temperature range of 200÷230°C. To that end a Testo thermal imaging camera was used, flexural strength of the combined components was tested as well as the received weld was observed under a stereoscopic microscope. Conducted studies showed that the best results of joint are obtained during welding at 220°C and 230°C, while lower temperatures did not fully perform their function during the process of joining the pipe elements.

Titanium and its alloys have significant uses in the biomedical, chemical, and aerospace industries. In this article, the current and gas flow rates were varied using Taguchi’s experiment design. The mechanical properties of the welded joint made using tungsten inert gas (TIG) welding and Ti6Al4V ELI as filler metal was characterized using the microstructure, microhardness, and tensile strength. The joint was classified into three regions, namely, fusion zone (FZ), heat affected zone (HAZ), and base metal (BM). Results show martensitic microstructure within the fusion zone (FZ) and the heat affected zone (HAZ), which resulted in an increased hardness within the fusion and heat affected zone.