Effects of coal tar pitch addition on the wear behavior of carbon/carbon composites

Effects of coal tar pitch addition on the wear behavior of carbon/carbon composites

Carbon/carbon (C/C) composites are acknowledged as high performance materials because of their good mechanical properties such as wear resistance, even at the higher temperature, due to their low thermal expansion [1-5]. Their hardness and light weight in addition to their superior mechanical properties at high temperature make C/C composites the best material to make brakes for aircrafts and other high weight vehicles. Accordingly, a number of studies have been conducted on the performance of C/C composites brake [6-9]. Generally, C/C composites are produced by the carbonization of the matrix precursors of carbon composites. However, some defects, such as porosity and micro-cracks, are also induced during carbonization, and these defects degrde the mechanical properties. Therefore, various methods have been adopted to reduce the development of defects during the manufacture of C/C composites [10-14]. On the other hand, coal tar pitch extracted from the recycling of petroleum-based fuel is relatively inexpensive to manufacture; therefore, it is extensively used as a source of carbon precursors [15-16].