Testing and Evaluation of Polymer Welds—An Insight into the Common Techniques

Abstract

Mechanical deformation of the plastics depends on the temperature, time and viscoelastic nature. The duration of the applied stress and the overall stress history are the stages dictating time dependency. Temperature dependent plastics deformation is affected by the thermal properties of the plastics which typically vary for thermoplastics and thermosets. Temperature dependency basically controls the time for plastic deformation. Semicrystalline or glassy plastics exhibits weaker viscoelastic nature at temperatures below their glass transition temperatures (Tg). It is essential to analyze the semicrystalline plastics for time-dependency based analysis owing to their nature. Increased mechanical response during time analysis is recorded due to the increased temperature either by heat provided during deformation or by the external heat fluxes. Plastics reveal significant difference in the deformation mechanism as compared to metals.