Limiting Factors in the Spectrophotometric Analysis of Minor Components of Blended Metal Powders

The accuracy of chemical analysis of minor components of blended metal powders is dependent on good mixing conditions, representative sampling, complete sample dissolution, and sensitivity of measurement system.

An accurate, precise, and sensitive analytical procedure has been developed which facilitates the use of large sample sizes of blended metal powders and overcomes the difficulties of sample dissolution. The technique involves homogenization of the metal blends by arc melting in an inert atmosphere and analysis of the resulting arc-melted button and slag by atomic absorption spectrophotometry. Methods of eliminating interferences in atomic absorption determinations are discussed. Mathematicial correction can be applied in lieu of slag analysis which cuts down the analysis time by 50 percent. A mechanism for slag formation is proposed.