In order to improve the bearing capacity of water-lubricated bearings,the tribological properties of thermoplastic polyurethane (TPU) bearing materials were improved by the hydration of hydrogels under water lubrication conditions.Hydrogel particles were prepared by using polyvinyl alcohol,sodium alginate,chitosan and other materials,and hydrogel/TPU composites were prepared by melt blending.The friction and wear properties of the composites were tested under loads of 0.3 MPa and 0.5 MPa.The wear surface morphology was observed by laser interference surface profiler and scanning electron microscope,and the wear mechanism was analyzed.The results show that the hydrogel particles can improve the lubrication condition of the friction pair through hydration lubrication,thereby reducing the friction coefficient and wear amount,and improving the friction performance of the composite.When the mass fraction of hydrogel is 4%,the composite has the best friction and wear properties,and compared with the TPU sample,the average friction coefficient reduction rate under the working conditions of 0.3 MPa and 0.5 MPa is 52.31% and 43.94%,respectively.This research provides a method for developing high performance materials for water lubricated bearings.