Roughness, Wear and Thermal Analysis of UHMWPE Nanocomposites Asacetabular Cup in Hip Joint Replacement

Reinforcement UHMWPE by nano additives represented by carbon nanotubes (CNTs) and nanohydroxyapatite (nHA) with four weight fractions (1, 2, 3 and 5%) has a vital role to the improvement of surface roughness and wear resistance of produced nanocomposites. A surface roughness of new nanocomposites was decreased with an increasing weight fraction of each additive especially with CNTs due to the larger surface area of this nanofiller compared with nHA particles that achieve lower area. The results of wear rate indicated the reduction in this rate with reinforcing and this reduction increases with an increasing weight fraction of each additive especially with nHA due to the better filling of the voids by HA particles compared with CNTs that have a hollow structure and may be left some holes in the bulk composite. The calculated volumetric rate also gave the same results as in weight loss as a function to the weight fraction of additives. The density was increased for prepared nanocomposites due to filling the pores compared with pure UHMWPE which has many holes filled by air. The increasing in density for UHMWPE/nHA composites was higher than UHMWPE/CNTs composites due to the good filling of the pores. Thermal analysis was done for prepared nanocomposites and the results gave rising in melting and crystallinity temperature for composites compared with pure UHMWPE.