Figure 2.

The specific strengths (SE) of various WLE candidate materials at elevated temperatures. Metal Matrix Composites (MMC) have initially high SE, but it rapidly decreases with increasing temperature. Ceramic Matrix Composites (CMC) tend to have stable SE through a wide temperature range. In super alloys such as MMCs and other metals, SE decrease rapidly near the melting point. Advanced C/C Composites (ACC) and C/SiC composites generally exhibit high melting points and low densities and maintain high SE over a wide temperature range. While having a generally lower SE, ceramics can potentially exhibit constant strength. There are some ceramics of interest above 1500 °C, such as ZrC, that have comparable melting points to ACC materials and are mechanically stable [14].