Scientific and Industrial Complex “Supermetal” JSC, Moscow, Russia

D. S. Tykochinskiy, Leading Researcher, e-mail: Tykochin@yandex.ru
V. V. Vasekin, Chief Executive Officer

S. D. Levchenko, Chief Metallurgist

The influence of alloying elements on the properties of gold-based alloys is studied in this paper. The purpose of the study was to establish the regularities of the gold color changing during the process of introduction of one or several alloying elements into the alloy: silver, copper, platinum, palladium, etc. A spectrophotometer with a spherical geometry of measurement was used to obtain the information about the color. The results are shown as the coordinates in the standard L*a*b* color space. The values of the chromaticity coordinates of gold alloys smoothly decrease with the increasing of the content of platinum or palladium. According to this, the yellowness index decreases. The received data make it possible to analyze the results of experiments. During the development process of gold alloys for dentures, there has been substantiated to limit the content of platinum and palladium to the specific level, on which the alloys color is still perceived as yellow.

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