Analysis of Metallic Glass Sample Including Niobium, Boron and Silicon by Microwave-Assisted Dissolution/Inductively Coupled Plasma-Optical Emission Spectrometry Using Hydrofluoric and Nitric Acids Mixture

Abstract

Metallic glasses containing iron, cobalt, niobium, boron and silicon were analyzed. The samples could be dissolved only with a mixture of hydrofluoric acid and nitric acid. After a sample dissolved, metallic elements were determined by inductively coupled plasma-optical emission spectrometry (ICP-OES). Conventional ICP-OES instruments were not employed because hydrofluoric acid attacked the plasma torch, chamber and nebulizer, which were made of quartz or glass. When a sample solution contained hydrofluoric acid, hydrofluoric acid was removed by heating with sulfuric acid. However, this removal technique led to a loss of boron and silicon. By a microwave-assisted dissolution procedure with a mixture of hydrofluoric acid and nitric acid, boron and silicon were not vaporized. A hydrofluoric acid resisting ICP-OES instrument was employed for elemental determination. The total values of all the elements determined were almost 100%.