③Waxyaabaha dhoobada ah ee ugu badan ee la isticmaalo tan iyo qarnigii 21-aad, dhoobada aan xabadu karin ayaa si degdeg ah u horumaray, waxaana jira noocyo badan, oo ay ku jiraan alumina, silicon carbide, boron carbide, silicon nitride, titanium boride, iwm, oo ay ku jiraan alumina ceramics (Al₂O₃), Silicon carbide cera...