EFFECT OF ADDING BORON CARBIDE (B4C) TO POLYMER FOR PRODUCING SURFACE COMPOSITE BY FRICTION STIR PROCESSING

Abstract

Friction stir processing (FSP) is a new solid state technique, it is employed for theimprovement of the mechanical properties of a material and the production of surface layercomposites instead of conventional processing technologies. This research aims to study theability of applying Friction Stir Processing (FSP) to modify the surface of high densitypolyethylene (HDPE) reinforcing by B4C with a particle size of 0.4?m, Groove in themiddle of HDPE surface made to fill by B4C. Varity in the groove depth (0.6, 1.2 and1.8)mm used according to B4C ratio on HDPE substrate particles. Friction stir process wascarried out, using tool with cylindrical shape of pin and shoe tool to produce surface layercomposite. The effect of processing parameters including rotational and transverse speeds onthe mechanical properties of composite layer was studied. Wear test results show apronounced improvement in wear resistance of HDPE surface through reinforcementadditions of B4C at a ratio (5%, 10% and 15% ), where wear rate improved by (60%, 71%and 63%) respectively, as compared with as received HDPE, the surface compositeHDPE/B4C have good wear resistance. Hardness test results indicate that the hardness ofcomposite layer reinforced with (5%,10% and 15%) particles improved by( 26%, 35% and28% )respectively as compared with received HDPE. OM revealed that high tool rotationalspeed resulted in homogeneous distribution of B4C particles and vice versa.