Study On The Mechanical Properties Of PVC/Al₂O₃ Nano-Filler Composites

In this thesis, the mechanical properties of PVC/Al₂O₃ nano-filler composites were researched. And the relationship between microscopic deformation mechanisms and macroscopic mechanical properties was investigated by micromechanics method and finite element methods.Polyvinyl chloride (PVC) composites filled with nano-Al_O3 were prepared by melt-blending process, also of which the mechanical properties were tested according to the Testing Standards. The results indicated: with the increase of percentage of nano-Al_O3 filled in PVC bulk, the Elastic Moduli and Impact Strength of composites increased, on the other hand, the Tensile Strength first increased then decreased, and the Poisson Ratio was almost constant. Also judged from the results, it was more precise to use the strain gauge than stretcher method.On the basis of Eshelby's inclusion theory, the equivalent Young's moduli of PVC/Al₂O₃ nano-filler composites was calculated through Energy Method. The difference between experimental value and theoretical value increased with the rise of nano-Al₂O₃'s percentage. So it was very necessary to disperse uniformly nano-Al₂O₃ in PVC bulk.Finally, the microscopic deformation mechanisms of PVC/Al₂O₃ nano-filler composites were investigated by the use of Ansys FEA software, based on which the effects of cavitation phenomena, the size of nano-Al₂O₃'s diameter and filled content on macroscopic mechanical properties of composites were discussed. The simulation results showed good consistency with the experimental results.