A Comparison of the Microstructure and Corrosion of Commercial Purity Titanium and Titanium-Aluminium-Vanadium Alloy Modified with Palladium and Ruthenium and Processed by Powder Metallurgy

The increasing demand for advanced materials in oil and gas exploration has driven renewed interest in modified Ti-6Al-4V alloys, particularly those doped with noble metals such as palladium and ruthenium. This study investigates the microstructural and corrosion behaviour of palladium- and ruthenium-modified commercial purity titanium (cp-Ti) and Ti-6Al-4V alloys fabricated via hot isostatic pressing (HIP) of 150–500 µm powders. Results reveal a non-uniform distribution of the noble metals, with enrichment at interparticle boundaries under the applied HIP conditions. Tailoring of microstructures was achieved by varying powder size and HIP parameters, with distinct β-phase morphologies observed between palladium- and ruthenium-modified samples. Palladium additions demonstrated superior corrosion resistance compared to ruthenium, highlighting the influence of dopant selection on alloy performance. The findings underscore the importance of powder metallurgical approaches for noble metal doping, offering pathways to microstructures and properties unattainable through conventional melt and wrought processing. This work emphasises the need for continued development of simulant protocols to bridge laboratory studies with field applications.