Investigation of Microstructural Characteristics and Mechanical Properties in Platinum-Rhodium Alloy Strengthened by Zirconium and Yttrium

In pursuit of enhancing the high-temperature service performance of Pt-10Rh alloys, this study focuses on the preparation of two Pt-10Rh-based alloys through the incorporation of reinforcing elements zirconium and zirconium-yttrium. The investigation into the microstructure, mechanical properties and strengthening mechanisms of the alloys involved the utilisation of analytical tools such as an optical metallographic microscopy (OM), X-ray diffraction (XRD), selected area electron diffraction (SAED), energy-dispersive X-ray spectroscopy (EDS) and tensile testing, coupled with first-principle computational analysis methods. The research results indicate the presence of Pt 5 Y precipitate phase and zirconium yttrium oxides in Pt-10Rh-0.5Zr-0.2Y alloy, but not detected in Pt-10Rh-0.5Zr alloy. It was found that adding a small amount of zirconium and yttrium elements to Pt-10Rh alloy can significantly enhance the mechanical properties at room temperature and 1300°C, especially the composite addition of zirconium and yttrium elements, which can also improve the high-temperature plasticity of the alloy. The strengthening mechanisms of zirconium and yttrium elements on Pt-10Rh alloy are mainly solid solution strengthening and second phase strengthening. The relationship between the mechanical properties of platinum-rhodium based alloys and their valence electron structure was discussed. The zirconium and yttrium reinforced platinum-rhodium based alloy studied in this work can replace Pt-10Rh alloy in certain fields.