Some physical properties of platinum-rhodium alloys

Abstract

In a continuation of the study at the Bureau of the metals of the platinum group, a series of platinum-rhodium alloys containing approximately 10, 20, 40, 60, and 80 percent rhodium was prepared from pure platinum and pure rhodium. The melting point, hardness, density, electrical resistivity, temperature coefficient of resistance, and thermal electromotive force against platinum were determined for each alloy. The microstructure of each alloy appeared to be that of a solid solution. The particular qualifications of the alloys containing 20 to 40 percent of rhodium, for use as resistance furnace windings for service at high temperatures, are discussed.