Trade Analysis of Strength and Wear Resistance of Gold-Based Alloys Containing Modifying Admixtures

Abstract

Abstract:The authors of this article have studied physical and mechanical properties of several gold alloys rating 585 and 375. Modern scientific studies demonstrate a significant influence of different modifying admixtures on the properties of gold-containing alloys. For comparison purposes they've chosen 15 jewelry gold-based alloys with different chemical composition and impurities i.e. Ga, Co, B, Si, Zr, Mn, or without them. To conduct the study they've used all available physical and mechanical methods. The alloys were tested for hardness after casting, after aging, the tensile and breaking strength as well as for relative wear resistance. The results of each alloy were analyzed individually and also in comparison with others. The purpose of the study was to identify alloys with the most optimal hardness, strength and wear resistance. Keywords: trade analysis, gold alloys, alloy admixture, mechanical properties, physical properties. IntroductionThe article contains the results of studies of physical and mechanical properties of gold-based alloys containing modifying admixtures. To compare the quality of gold-based jewelry alloys they've studied 15 jewelry alloys the chemical composition of which is given in the table below. No. 7 alloy was chosen as the main reference alloy. The given alloy meets the requirements of GOST 30649-99 and is deemed to be "traditional" due to its common use by domestic jewelry enterprises. The main drawback of this alloy is insufficient quality of the jewelry, whereat, in aggregate, inherent characteristics of the alloy meet the technological and consumer requirements both during manufacture and in service. The main alloy drawbacks are induced by dendritic segregation during casting due to irregular arrangement of golden and silver elements, which reduces the reliability of finished products, and by rather high surface roughness and low characteristics of mold filling, which, from the technological point of view, makes the process of jewelry manufacture quite complicated.