Tungsten, molybdenum, tantalum ndi niobium ndi zida zofunika kwa mafakitale oyendetsa ndege ndi chitetezo chifukwa cha katundu wawo: kukhazikika kwa kutentha kwapamwamba, kachulukidwe ndi mphamvu zamanjenje, machinability awo abwino kwambiri, komanso chitetezo cha radiation.