Wear Mechanism Of PEEK With Artificial Closure Material Under Cross-shear Effect

With the rapid development of science and technology,the market demand for artificial joints has also increased,and total joint replacement has gradually become an effective means of treating a series of joint diseases.As the demand for joint replacement increases and the life expectancy increases,the performance requirements for artificial joint materials also change.In order to improve the service life of artificial joints,some new artificial joint materials including PEEK and CFR-PEEK have been developed,and the study of the cross-shear effect of these new materials is of great significance for the evaluation of the performance of artificial joint materials.In this paper,the wear mechanism of PEEK and CFR-PEEK under the effect of cross-shear is studied in depth by a series of cross shear ratio and wear test under contact pressure conditions,and compared with the traditional artificial joint material ultra-high molecular weight polyethylene.Whether these two materials are suitable for artificial joint materials and their advantages and disadvantages as artificial joint materials.In the experiment,the two new materials were subjected to the wear test for 3 hours by the multidirectional pin-on-plate wear machine.The values of the cross shear ratio and the contact pressure were also the parameters within the actual physiological range of the human body.Wear is the main factor in the late failure of artificial joint replacement,and the cross shear ratio is an important parameter to measure the wear performance of artificial joint materials.In the experimental study on the wear properties of joint materials by cross shear ratio parameters,the experimental results show that PEEK has the same wear effect related to cross-shear as UHMWPE,while the material of CFR-PEEK does not show significantcross-shearing effects in the experiment.In addition,under the same conditions,PEEK has poor wear resistance compared with UHMWPE,and its wear coefficient is about 8 times that of UHMWPE,while CFR-PEEK has significant wear resistance,and its wear coefficient is about UHMWPE.50%.Therefore,the materials of CFR-PEEK are expected to be suitable substitutes for UHMWPE in artificial joint applications.When the human body is in different motion states,the load on the joint surface of the joint is different.In the experimental study of the contact pressure parameters on the wear performance of joint parameters,the experimental results show that the wear coefficient of PEEK is higher than the wear coefficient of CFR-PEEK,the wear coefficient is about 6 times that of CFR-PEEK,and the wear coefficient of PEEK and CFR-PEEK increases as the contact pressure increases.However,the wear coefficient of UHMWPE shows a decreasing trend with the increase of contact pressure.It can be concluded that the wear performance of the material is not directly related to the contact pressure.Under the large contact pressure,the wear performance of CFR-PEEK has no advantage compared with UHMWPE,but CFR-PEEK is under large contact pressure.The wear performance has large variables.Therefore,CFR-PEEK materials are suitable for making artificial joints that are subjected to lower contact pressures.