THE ANALYSIS OF CHROMIUM, COBALT, IRON, NICKEL, NIOBIUM, TANTALUM, TITANIUM AND ZINC IN CEMENTED TUNGSTEN CARBIDES WITH COBALT AS A BINDER BY INDUCTIVELY-COUPLED PLASMA-ATOMIC EMISSION-SPECTROMETRY

Inductively coupled plasma atomic emission spectrometry (ICP-AES) was applied as a rapid routine method for the analysis of cemented tungste n carbides. Chromium, cobalt, iron, nickel, niobium, tantalum, titaniu m and zinc were selected as major, minor and trace constituents in the material investigated. In the first step, the sample was treated with hydrochloric and orthophosphoric acid. The second step consisted of t he simultaneous addition of hydrofluoric and nitric acids. Cemented tu ngsten carbides dissolved completely, leaving only minor quantities of carbon in the solution. Multiple linear regression proved to be very effective in the search for interfering elements. Using simple acid ba sed standards, all the elements investigated could be determined indiv idually from the complicated matrix using an appropriate method of cal culation. The method described was successfully applied to real type c ommercial samples. The advantages of the ICP-AES method in comparison with tile XRF-method are discussed.