EFFECT OF GRAPHITE PARTICLES ADDITION AND PROCESS PARAMETERS ON THE MECHANICAL PROPERTIES OF POLYETHYLENE/GRAPHITE SURFACE COMPOSITE FABRICATED BY FRICTION STIR PROCESSING. (2016). Journal of Engineering and Sustainable Development, 20(3), 155-167. https://jeasd.uomustansiriyah.edu.iq/index.php/jeasd/article/view/669