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

الملخص

Friction stir processing (FSP) is a new solid state technique, it is employed for the
improvement of the mechanical properties of a material and the production of surface layer
composites instead of conventional processing technologies. This research aims to study the
ability of applying Friction Stir Processing (FSP) to modify the surface of high density
polyethylene (HDPE) reinforcing by B4C with a particle size of 0.4?m, Groove in the
middle of HDPE surface made to fill by B4C. Varity in the groove depth (0.6, 1.2 and
1.8)mm used according to B4C ratio on HDPE substrate particles. Friction stir process was
carried out, using tool with cylindrical shape of pin and shoe tool to produce surface layer
composite. The effect of processing parameters including rotational and transverse speeds on
the mechanical properties of composite layer was studied. Wear test results show a
pronounced improvement in wear resistance of HDPE surface through reinforcement
additions 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 composite
HDPE/B4C have good wear resistance. Hardness test results indicate that the hardness of
composite layer reinforced with (5%,10% and 15%) particles improved by( 26%, 35% and
28% )respectively as compared with received HDPE. OM revealed that high tool rotational
speed resulted in homogeneous distribution of B4C particles and vice versa.