The Moly-D element is a dense cermet material consisting of MoSi2 and an oxide, glassy phase component.
Moly-D elements have the ability to withstand oxidation at high temperatures by forming a protective layer of quartz on its surface. If this glassy phase should be exposed to contaminants, a lower melting phase forms. This material literally drips off the element exposing more molybdenum disilicide on which a new protective oxide layer forms.
Moly-D elements become somewhat ductile at approximately 1200ºC (2190ºF).