Preliminary investigation of slurry erosion behaviour of tantalum

Frequent premature failure of the ISIS spallation neutron source target prompted the investigation of previously unexplored aqueous slurry erosion response of pure tantalum (Ta) with an overarching aim to improve the service life of the target; hence, reducing the disposal of radioactive waste. Understanding such response of Ta is highly significant to many other applications such as nuclear and chemical processing. In this study, powder-metallurgically manufactured pure Ta was investigated with the help of an impinging jet aqueous slurry erosion apparatus using silicon carbide particles at a range of concentration, impact velocity, and incident angle. Results revealed a unique material removal mechanism consisting formation of extensive voids/cavities all over the eroded surface. These mechanisms are discussed considering the theories of solid particle erosion and the grain boundary sliding behaviour of Ta under localised indentation loading.