Abstract
Metal/Metal universal joints reinforced by carbon fibers had been proposed to save the energy and to enhance the mobility of mover machines. The ductile fracture occurred at aluminum part in the Ti/Al joint with carbon fiber reinforcement (CFR). Although the tensile strength (σ_b) was slightly reduced, its strain (ε_b) and maximum strain (ε_f) of the CFR-Ti/Al joint with ductile fracture were 1.8 and 2.5 times higher than those of the Ti/Al joint with brittle fracture Ti/Al joint without CFR because of huge static and dynamic friction force induced by the high resistance to pull out narrow carbon fibers, respectively. CFR elongated not only theε_b and ε_f , but also enhanced the initial modulus value of dσ/dε. Based on the mixture law, increasing the volume fraction of carbon fiber enhanced the stiffness. CFR didn't increase the tensile strength (σ_b) much since the joint sample was melted and solidified, the process increased the grain size, resulting in tensile strength decreasing although strain and modulus were increased.
