om the group consisting of Hafnium, Rhenium and Lanthanides, in particular Cerium, [0024] (d) and a balance of Tantalum [0025] The alloys preferably provide for a uniform beta structure, which is uniform and corrosion resistant, and have the ability for conversion oxidation or nitridization surface hardening of the medical implant or device. [0026] The tungsten content is preferably between 0,1 an