ʻO nā metala refractory ka mea maʻamau i kēlā mau metala me kahi helu heheʻe ma mua o 2200K, e like me Hf, Nb, Ta, Mo, W a me Re, a i ʻole nā metala hoʻololi a pau o ka pūʻulu IV i ka pūʻulu VI o ka Papa Manawa, ʻo ia hoʻi nā metala. Ti, Zr, V a me Cr me nā helu heheʻe ma waena o 1941K a me 2180K.Hōʻike kēia mau hiʻohiʻona ʻē aʻe i ka uila, uila, corrosion resistance noi i ka ambient temperature, mechanical properties, fabricability, economic factors, and special properties for chemical process applications compared to more traditional materials used in the process industry.ʻOkoʻa nā metala liʻiliʻi e like me tellurium, cadmium, bismuth, indium zirconium etc.