UHMWPE / AL2O3 SYNTHESIS AND MECHANICAL PROPERTIES EVALUATION

Abstract

UHMWPE being similar to HDPE has got more interesting properties like chemical stability and most importantly the abrasion resistance property. The applications of UHMWPE among important sectors have drawn researcher’s attention towards improving the properties of UHMWPE by filling it with micro and nano particles (ceramic oxides). In this work, the major concentration is on developing UHMWPE composites reinforced with Al2O3 and ZnO nano particles and analysing the mechanical, tribological and microstructural characteristics. The nano reinforcements were synthesized using sol-gel process and used in the study. Mechanical characterization was done through standard procedures with specimen standards corresponding to ASTM. Compositions selected for the study were 2.5, 5, 7.5, 10 and 12.5 % of Al2O3/ZnO NPs along with UHMWPE as base matrix. Density test was conducted using the standard procedure and porosity in percentage was calculated. It was clearly observed that with an addition of 12.5% NPs, the porosity increases rapidly because of the pore nucleation due to increased surface area and shrinkage due to volume contraction because of agglomeration. Hardness test was conducted on Vicker’s hardness tester and for both the reinforcements an increase in hardness with an increase in NP fillings was seen. Although, at 12.5% NP, there was no such improvement in hardness. This directly is related to the porosity of the composite at 12.5% NP. Impact and compression strength results also show the same trend.