Effects of micro-Al(OH)3 and nano-SiO2 on wear behavior of GF/epoxy composites in high-friction velocity

Abstract

Effects of micro-Al(OH) ₃ powders on wear behavior of GF/EP composites are studied in friction velocity from 15 to 45 m/s. The results show that friction coefficients change insignificantly with increase of loads and addition of powders, but change significantly with the variation of friction velocity. Abrasion rates increase dramatically with the increase of friction velocity and load. The addition of nano-SiO₂ increases the abrasion rate under the same load, the addition of Al(OH)₃ powders decreases the abrasion rate. The wear mechanisms are adhesive and fatigue, which do not change with addition of either micro-Al(OH)₃ powders or nano-SiO₂. In the previous study, abrasive friction is the major wear mechanism in lower velocity friction condition. Different from low-velocity friction, the friction between the GF/EP composites and the transfer film is predominating in high-friction velocity, which results in dramatical increase in wear rate and decrease in friction coefficient in higher friction velocity. The effects of Al(OH) ₃ powders on wear rate are attributed to the heat absorption when Al(OH) ₃ powder decomposes, which is testified by the endothermic effect between 200^°C and 300^°C in DSC curves.