Investigation of the Structure and Corrision Behavior of Alloys in the Ti-Ta-Cr System,

Polythermal corss sections of the Ti-Ta-Cr system with a ratio of TaCr 13 11 31 were constructed. As the tantalum content in the alloys increases the stability of the beta-phase increases and the eutectic transformation is shifted to the region of higher overall tantalum and chromium content and lowest temperatures. As the tantalum content increases the corrosion rate for both quenched and annealed alloys decreases. The ternary Ti-Ta-Cr alloys with a ratio TaCr 31 and binary Ti-Ta alloys with 20 or more Ta become corrosion resistant in a 5 HC1 solution at 100C. Alloying titanium with chromium reduces its corrosion properties in HC1 solution. The corrosion rate increases as the chromium content increases for both quenched and annealed alloys.