Preparation of PTFE composites filled by BaSO₄

A method of combining cold molding with sintering was adopted to prepare BaSO₄/PTFE composites. The influences of BaSO₄ particles with different contents and granular size on the properties of the BaSO₄/PTFE composites were investigated. The results show that the contents and granular size of BaSO₄ particles greatly influence on the properties of the composites. The wear resistance ability of composites is optimal, and the corresponding wear weight loss of the composite is about 100 times lower than the nature PTFE, when the size of BaSO₄ is 44 μm and the mass fraction of BaSO₄ is 40%. The SEM analysis of wear surface indicates that the wear mechanisms of composites change from main adhesion wear to abrasive wear with possible fatigue wear, with the increase of fraction of BaSO₄ particles.