Research On The Construction Of Porous TC4/Hydrogel Integration Bionic Cartilage Material And Biotribology

Artificial joint replacement is a successful clinical treatment for osteoarthritis.Nevertheless,conventional prosthesis materials for artificial joints are prone to wear and tear.To address this issue,a possible solution is the utilization of a soft-hard integrated artificial joint that mimics the natural articular cartilage-bone integration characteristics.Hydrogels have demonstrated great potential as a substitute for cartilage,as they closely mimic the structure and function of natural articular cartilage.The development of biomimetic cartilage materials has been hindered by limitations such as insufficient mechanical properties and poor matrix bonding strength,preventing their widespread use in the clinical field.To overcome this,it is crucial to create materials that possess high load-bearing and low friction abilities while also integrating cartilage and bone materials with high bonding strength.This thesis delves into the creation of a biomimetic cartilage material using metal3D printing technology and the exceptional qualities of articular cartilage.The process involves the construction of a titanium alloy substrate with a porous structure,followed by coating it with a PVA/PAA/Graphene composite hydrogel through acid etching and polydopamine（PDA）modification.The material features a composite structure that combines soft and hard components,resulting in high load-bearing capabilities and low friction.Notably,the material’s interfacial bonding strength is comparable to that of natural joints.The incorporation of PAA and Graphene into the hydrogel matrix results in a significant improvement in its mechanical properties.The tensile stress and tensile modulus values increase to 10.19 MPa and 3.11 MPa,respectively.Moreover,the hydrogel matrix exhibits a high compressive strength and compression modulus,reaching 5.01 MPa and 4.93 MPa,respectively.These findings suggest that the hydrogel matrix is capable of effectively withstanding deformation under large loads.The results of the experiments show that the friction coefficient of biomimetic cartilage material is influenced by its level of permeability.When the material has low permeability,it prevents the fluid phase from exuding and allows the material to retain a significant amount of fluid internally.This leads to the formation of a hydrostatic pressure that can bear a substantial amount of the load.The material improves anti-deformation ability and reduces wear during operation,while maintaining a friction coefficient similar to natural cartilage.The friction coefficient of biomimetic cartilage material first increased and then decreased with the increase of load,and gradually increased with the increase of sliding rate.Calf serum is a rich source of albumin and peptides that can generate a lipid lubrication layer at the contact interface,resulting in a reduced resistance when sliding.This lubrication layer has been found to contribute to a low friction coefficient of as low as 0.027.Moreover,soaking the bionic cartilage material in Fe³⁺can lead to internal complexation,which enhances polymer network crosslinking,effectively resisting deformation in the friction process and improving wear reduction.Further continuous friction tests have been conducted to validate the exceptional wear resistance capabilities of the bionic cartilage material.The results show that even after 500,000 friction tests,the material’s surface exhibited minimal wear,and the friction coefficient remained low.The results of the torsional friction experiment showed that as the load and torsion angle increased,so did the friction torque of the Co Cr Mo-Hydrogel pair in the’hard-soft’contact.In contrast,the Hydrogel-Hydrogel friction experiment in the’soft-soft’contact showed a reduction in torque over time,with the final torque being lower than that of the’hard-soft’friction pair.By the end of the 100,000 cycles experiment,the friction torque had dropped to 0.2N/m.In this thesis,there are 77 figures,12 tables and 102 reference articles.