Preparation of Oxidation-Resistant Ultra High Melting Temperature Materials and Structures Using Laser Method.

摘要

This report describes laser and hybrid (laser + microwave) processing of ultra-high temperature ceramic (UHTC) materials. We have successfully developed new UHTC based composite materials that are capable of dealing with harsh environment encountered by hypersonic cruise and atmospheric re-entry vehicles. The advanced ZrB2-metal composites provide good performance at much lower densities than other UHTCs like hafnium diboride (HfB2) and refractory metals such as rhenium and tungsten. In addition, these ceramic- metal composites (cermets) reduce the likelihood of mechanical failures by increasing fracture toughness and thermal shock resistance that are inherent properties of mostly brittle ceramics, but at the same time enhance some material properties like hardness that usually lack in metals.