Improvement of technology for the production of jewelry wire from platinum alloys

The paper presents the findings of research on the production of wire from 850 and 585 platinum-based alloys intended for use in jewelry chains. The chemical compositions of two novel jewelry alloys of 585 platinum-containing modifying additives of rhodium and ruthenium are proposed and patented. An analysis was carried out to evaluate the existing section rolling and drawing schedules for the three platinum alloys to identify more efficient drafting methods, with a focus on reducing the labor intensity of metal deformation processes and minimizing the force parameters. A computer model of section rolling for the studied jewelry alloys, based on 850 and 585 platinum, was developed to analyze the shape variation and force parameters of the process and to propose a new deformation schedule for the studied alloys with the accepted reduction distribution per pass. The new deformation schedule was characterized by a more uniform reduction distribution per pass than that observed in the existing schedule, allowing the number of rolling passes to be reduced due to their redistribution. In order to determine the rolling force and to model the process, an approximation formula was used to calculate the time resistance, which is dependent on the total degree of compression. By using proprietary software and computer simulation, the parameters of wire drawing with a diameter of up to 0.25 mm from the studied alloys were calculated, which allowed the deformation and force parameters to be assessed when implementing the proposed drafting schedule. In addition, it was established that the drawing process exhibits a sufficiently high safety factor and low power consumption. It is therefore recommended that the process be subjected to industrial testing. The findings of this research can be recommended for improving the technology of wire manufacturing from the 850 and 585 platinum alloys intended for jewelry chains.