Mechanical and tribological properties of polyamide 6–polyurethane block copolymer reinforced with short glass fibers

Reinforced polyamide 6–polyurethane (PA6–PU) block copolymers with different short glass fiber proportions were prepared by monomer casting (MC) technology. The mechanical and tribological behaviors of the reinforced composites were studied. The friction and wear experiments were tested under ambient conditions in a friction machine with the chromium steel ball sliding on the surface of the composites at rather high sliding speeds of 500, 1000 and 1500 r/min and loads of 78.5 and 157 N, respectively. Tensile strength of the composites increased with the addition of glass fibers, but notch impact strength decreased. The glass fiber reinforcement was found effective in reducing the coefficient of friction and the wear rate. The effect of the applied load and sliding speed on tribological properties of the composites was explored in this study. The load and sliding speed showed stronger effect on the wear rate of the composites. The results showed that both the coefficient of friction and wear rate values increased with the increasing of load. With the increasing of sliding speed, the coefficient of friction of the composites decreased, while the wear rate values increased. Microstructure of worn surface of the tested composites was inspected by scanning electronic microscope (SEM) and wear mechanism of the reinforced composites was studied.