Corrosion Of Ceramics In Aqueous Hydrofluoric Acid

A variety of commercially available ceramic-based oxides, carbides, nitrides and borides were evaluated for chemical attack in an azeotropic aqueous hydrofluoric acid (HF) test protocol at 90 deg C. Weight change measurements and microstructure analysis showed that HF corrosion in polycrystalline ceramics generally occurred at grain boundaries by the dissolution of grain boundary phases although the bulk single crystal may inherently resist attack.