The determination of columbium in rustless and heat‐resisting steels. Part I

Abstract

A procedure is described for the determination or columbium in rustless and heat‐resisting high chromium nickel steel. Provision is made for the presence of tungsten, titanium, and molybdenum. By a slight adjustment of conditions, tungsten precipitation is quantitative and a simultaneous determination may be made. The efficiency of hydrolysis separations is discussed and a method of sulphurous acid hydrolysis from divalent iron solution recommended. An examination of the separation of columbium from tungsten by the magnesia method1 has indicated that errors are introduced due to the formation of colloidal columbic acid which prevents a quantitative separation of these two metals. Colloid formation is overcome by using a modified wash liquor. This paper is the first of two to be published on this subject.

Ferrous Metallurgy

“…This secondary radiation is monochromated and the intensity of the lines of the different elements measured by means of a Geiger-Müller counter (2, 50). Both types of direct-reading spectrometers represent methods and apparatus not available 6 years ago but now in daily use by chemists for research and production control.…”

Colorimetric Determination of Microgram Amounts of Tungsten in Uranium-Tantalum-Tungsten Alloys

“…Colorimetric methods for the determination of tungsten were investigated because of the need for a rapid and accurate procedure for the determination of about 0.5% of tungsten in uranium-tantalum-tungsten alloys. Analyses of these alloys had been made using a modification of a gravimetric method described by Bagshawe and Elwell (2), but the low tungsten concentrations and the difficulties encountered in separating the tantalum and tungsten made the gravimetric procedure long and tedious. Therefore, an independent method was sought which would provide reliable analytical results and be better suited for the low tungsten concentrations.…”