Research On The Wear Test Of Artificial Joint Materials UHMWPE With PEEK And CFR-PEEK

Today's population is aging more and more seriously,and the number of people suffering from joint diseases continues to rise.Many young people have serious joint wear and tear due to factors such as high work intensity.Replacement of artificial joints has become a very effective measure for the treatment of joint diseases.Because patients need to perform daily activities such as walking,squatting,going up and downstairs,the replaced artificial joints have high requirements on wear performance.In this paper,the wear properties of artificial joint materials are studied by changing the form of movement and the pressure.In this paper,high molecular weight polyethylene(ultra-high molecular-weight polyethylene,UHMWPE)and polyetheretherketone(PEEK)and carbon fiber reinforced polyetheretherketone(CFR-PEEK)are used as research objects,and UHMWPE/PEEK and UHMWPE/CFR-PEEK are respectively developed experimental study on the pin-plate wear under different contact stresses and cross shear ratios.By analyzing the wear volume and wear coefficient measured under different test conditions,combined with the surface topography analysis,the wear characteristics of the two material pairs were revealed,and the following conclusions were obtained:The wear test results show that,regardless of the contact stress,the wear coefficient of the pins in the UHMWPE/PEEK pair is much larger than that of the UHMWPE/CFR-PEEK pair,and the former is about 5 times that of the latter.The wear volume and wear coefficient of both are the smallest when the contact stress is 3.18 MPa.With the increase of the cross shear ratio,the wear volume and wear coefficient of the UHMWPE/PEEK matching pin change irregularly,while the wear volume and wear coefficient of the UHMWPE/CFR-PEEK matching pin increase with the cross shear ratio.The former wear coefficient has a strong dependence on the change of cross shear,while the latter wear coefficient is not greatly affected by the cross shear ratio between 0 and 0.087.By observing the surface topography of the samples before and after the test combined with the surface topography to characterize the Sa,Ssk and Sku parameters,it was observed that when the contact stress of the UHMWPE/PEEK pair was 3.18 MPa,the surface was dominated by troughs,and the oil storage capacity was better.The phenomenon that the wear coefficient decreases with the increase of the contact stress is explained.When the cross shear ratio is different,the Sa of the pins are different,and the shape and area of the surface protrusions change without regularity.However,the Sa of the UHMWPE/CFR-PEEK pair is smaller than the former regardless of the test conditions,and the surface morphology parameters are less affected by the test conditions,and the surface is flatter.To sum up,the wear performance of UHMWPE/CFR-PEEK pair is better than that of UHMWPE/PEEK pair under different contact stress and different cross shear conditions used in this paper.