The condition of the consumables is a key factor determining the waste reduction in the welding processes and the quality of the welded joint. The paper presents the results of tests of four types of flux-cored wires dedicated for welding high-strength steels, stored for 1 month and 6 months in Poland in two urbanized areas: in a large seaside city (Gdańsk) and in Warsaw, located in the center of the country. The wires were subjected to macroscopic and microscopic (stereoscopic, SEM) observations, EDS analysis, technological tests assessing elastic properties and targetability. The degree of degradation of the wires was also tested using resistance measurements. In order to assess the effect of storing wires on the weldability of steel, the diffusible hydrogen content in deposited metal was determined by high-temperature extraction. It was found that the storage caused changes in the surface condition of the wires, affected their elasticity and electrical properties, which affects the behavior of the wires during welding. A significant influence of storage conditions on the hydrogenation of deposited metal was found: in the case of three types of wires, the level of low hydrogen processes was exceeded and the maximum result was 15.18 ml/100 g of deposited metal. It was also found that copper-plated wire showed a significantly increased resistance to storage conditions compared to non-copper-plated wires.

Recently, stretchable triboelectric nanogenerators have attracted considerable attention as sustainable energy sources for emerging sensors and electronic applications. In this study, we fabricated a high-performance triboelectric nanogenerators (TENG) (SRC-TENG) with excellent stretchability based on a composite electrode composed of a silicone rubber and carbon nanotube (CNT). Our SRC-TENG is capable of 800% elongation and is structurally simple, robust, and easy to fabricate. Moreover, it exhibits excellent performance and delivers a maximum output of 3.52 W/m 2 at 100 MΩ, which is comparable to or even higher than those of most ultrastretchable TENGs reported. Furthermore, the output performance of the SRC-TENG is enhanced by optimizing the thickness of the composite in the range of 500-3000 μm. This increase was due to the increase in the interfacial area between the dielectric material and CNTs and the enlargement of the contact area. The fabricated SRC-TENGs show relatively high output performance even in their stretched state (e.g. less than ~ 30% decrease at 200% elongation) and demonstrate excellent long-term stability under a continuous loading of 50,000 cycles. We believe that our design principle for developing a high-performance TENG based on a composite electrode can be further expanded to other combinations of tribomaterials for various applications.