Effects of Welding Parameters and Pre-Heating on the Friction Stir Welding of UHMW-Polyethylene

摘要

The aim of this study was to investigate the weldability of UHMW-polyethylene via friction stir welding method. The samples were joined with single pass under 960-1960 rpm rotational speeds and 10-20 mm/min transverse speeds. In this study, three different heating processes were used. These processes are welding at room temperature, welding by pre-heating from the bottom of plastic samples at 50°C and 80°C with metal molding. A tensile test, durometer hardness test and an optical microstructure analysis were conducted on welded joint. In the experiments, a tensile strength of 72% was achieved in non-preheated welds whereas tensile strength of parent material was achieved approximately at an optimum value of 89% by pre-heating at 50°C. Pre-heating process enabled a homogeneous heat distribution by approximating the plastic material to fusing point in a short time and facilitated mixing and as a result welded joint of a supremer characteristic was obtained.