Development of segregated polyethylene/carbon black composites for embedded heating and strain sensing elements in electrofusion welded joints. Part I: potential assessment of segregated structures for strain sensing.

This electronic document is a “live” template. The various The quality control of welded joints is a crucial part of industrial production and can be done by their real-time monitoring. In this study, the potential application of high-density polyethylene-based composites with various carbon black (CB) addition (from 20 to 30 vol.%) for use as an embedded heating element and strain sensor was examined. The pyroresistive heating process was used to determine the impact of generated Joule heat during welding on the structure and piezoresistive properties of composites. It is shown that generation of Joule heat affects the crystallity of the polymer matrix and partially disrupts the conductive CB path, but that dependents on the CB amount. For lower amounts of CB conductivity decreases after welding, while for the highest CB amount conductivity increases. This phenomenon is related to particle-to-particle distance, which is lower if the volume is higher. Therefore, the best balance between pyroresistive and piezoresistive properties after heating was found as 25 vol.% of carbon black.