Study On Mechanical Properties And Abrasive Process Of Reinforced-Poly (Ether-Ether-Ketone)

Poly(ether-ether-ketone)(PEEK)is a new polymer material with excellent material properties,which has been widely used in aerospace,medical,industry and automobile fields.The hardness and modulus can be improved by introducing short fiber.The type and mass fraction of modified fiber have a vital influence on the mechanical properties of PEEK materials.In the field of high-end manufacturing,materials need not only excellent material properties but also high surface integrity through mechanical processing.However,the influence of modified fiber on the processing performance of PEEK material is not clear,and the material removal mechanism of modified PEEK material in the process of processing is still lack of systematic research.The surface quality of modified PEEK material after processing can only reach micron level,and there are few studies on the processing technology of higher surface quality.Therefore,this paper aimed at studying the influence of mechanical properties of fiber-reinforced-PEEK on its machining properties,deeply analyzed the influence mechanism of fiber types and mass fraction on its abrasive processing properties in lapping and polishing,and determined reasonable efficient and high surface quality processing technology for different fiber-reinforced-PEEK materials.The research results have important guiding significance for realizing efficient and high surface quality processing of PEEK materials and expanding its application field.The paper contains the following main research contents and conclusion:(1)In this paper,the nanomechanical properties of four kinds of fiber-reinforced-PEEK materials(carbon-fiber-reinforced PEEK with 10% mass fraction and 30% mass fraction,glass-fiber-reinforced PEEK with 10% mass fraction and 30% mass fraction)were studied using nanoindentation experiments.The results show that the nano-hardness and elastic modulus of PEEK can be improved by fiber modification.The larger the mass fraction of fiber is,the better the nano-mechanical properties are.The tensile properties of four fiber-reinforced-PEEK materials were studied using uniaxial tensile test.Due to the brittleness of the fiber,the fiber-reinforced-PEEK material was a brittle material.The tensile strength of PEEK material was improved by carbon fiber and reduced by glass fiber.The more fiber mass fraction,the more significantly influence on the tensile strength.(2)The lapping and polishing properties of modified PEEK were studied through the lapping experiments with different particle sizes silicon carbide abrasive paper and the polishing experiments with different polishing abrasives.During lapping,with the increase of abrasive paper mesh,the lapped surface quality of modified PEEK becomes better.The introduction of carbon fiber and glass fiber improves the hardness and elastic modulus of PEEK,which reduces the material removal rates but the lapped surface roughness.The higher the fiber mass fraction,the lower the material removal rate and the better the surface quality.During polishing,the surface quality of PEEK modified by silica sol polishing is poor,and there are still many scratches on the surface.After polishing with a mixed polishing solution of diamond powder and silica sol,the surface quality is greatly improved,and the surface roughness reaches 20 nm.(3)According to the research basis of grinding and polishing,the abrasive processing technology of different modified PEEK materials with high surface quality was developed.The process was rough lapping-precision lapping-polishing.After the optimized processing technology,the surface roughness Sa of the modified PEEK material was reduced to less than20 nm,realizing the high surface quality processing of the modified PEEK material.