Study On Preperation And Property Of C/C Composite For Artificial Finger Joints

Due to their characters of low density, high specific strength, excellent tribological property and high-temperature mechanical behavior, carbon/carbon (C/C) composites mainly used as high-temperature structural materials in the area of aerospace. In recent years, C/C composites is also used to make human hard tissue substitute biomaterials like artificial joints because of excellent biocompatibility and similar elastic modulus of human bone.In the present work, C/C composites used for artificial finger joints are fabricated by resin liquid impregnation method in different process conditions. The densification regularity, main mechanical properties of C/C composites, such as: flexural strength, compressive strength, elastic modulus, tribological behavior were investigated by experiments. It was discovered that: self fabricated C/C samples are close to some foreign C/C samples of brake discs on main mechanical properties.Experimental results showed that with increasing of densification cycles of C/C composites, the bulk density of samples increased, open porosity and densification efficiency is falling. Meanwhile, needle punched perform has higher densification efficiency than 3D braided perform due to its more diffusion paths, but its bulk density of final production remain low. By bending test and compression test, C/C composites have much lower elastic modulus than common metal materials. Samples carbonized in 1200°C showed higher flexural strength than which in 800°C 1000°C. Fracture types of C/C composites may display by pseudo-plastic failure and brittle failure, which depend on the combination between carbon fibers and matrix. Friction and wear experiments certified that C/C composites have excellent friction and wear behavior. For needle punched C/C samples, process parameters also influence their friction and wear property. With increasing of carbonization temperature, wear volume of samples increased, however, mass loss rate reduced. In addition, compared with needle punched structure, C/C samples with 3D braided structure have lower wear volume, mass loss rate, friction coefficient, and show more favorable friction and wear property.