Research On The Tribological Properties Of UHMWPE Modified By Glass Microspheres

Bridge bearing is an important part of large and medium-sized bridges.The polymer wear-resistant sliding plate is in the working condition of high normal pressure and linear reciprocating friction for a long time.Ultrahigh molecular weight polyethylene(UHMWPE)is a common material for bridge bearing sliding plate.With the rapid development of large and medium-sized bridges,higher requirements are put forward for its bearing capacity and tribological properties.The UHMWPE was focused by this thesis.The modification technology of UHMWPE was researched.The UHMWPE composites were prepared with different kind of fillers,and its mechanical and tribological properties were tested and analysed.The main results and conclusions are as follows:(1)HGM/UHMWPE composites with different amounts of HGM were prepared,and the mechanical and tribological properties of the composites were studied.The results show that the crystallinity and hardness of the material could be improved with the addition of HGM.When the HGM content is 1 wt% and 2 wt% respectively,the crystallinity and hardness reach the maximum.The wear gradually intensifies with the increase of HGM contents.The friction coefficient shows two different trends: monotonic increase at 82.5 MPa and first decrease and then increase at 103.9 MPa,respectively.(2)The mechanical simulation model of glass microspheres/UHMWPE is established by randomly distributing fillers,and the bearing and deformation of glass microspheres/UHMWPE are analyzed.The results show that the distribution of glass microspheres in UHMWPE matrix has little effect on the deformation under pressure,while has evident effect on the value of stresses.The error of the upper surface compression deformation and the error of the maximum von Mises stress caused by different distribution of glass microspheres are no more than 1.74% and 22.82%respectively.With the increase of specific pressure,the deformation and stress of the composites increase linearly.And the anti-deformation ability of composites under heavy pressure increased with the increase of the content of the glass microspheres.(3)PSM/UHMWPE composites with different PSM contents were prepared,and material properties and tribological properties of which were tested.The results show that the bearing capacity of UHMWPE was improved with the raising of PSM content.Compared with pure UHMWPE,PSM/UHMWPE has higher hardness and compressive strength.The hardness of the composites increases slowly with the increase of PSM content,and the compressive strength reaches a maximum of 43.6 MPa when the PSM content is 9 wt%.The addition of PSM can also significantly improve the friction and wear properties of the composites.The friction coefficient and wear rate of PSM/UHMWPE composites decreased first and then increased with the increase of PSM content.When the PSM content is 9 wt%,the friction coefficient and wear rate reach the minimum,and the reasons for this feature are deeply analyzed.