BATTELLE MEMORIAL INST COLUMBUS OH DEFENSE METALS INFORMATION CENTER
A study of the air contamination and protection for 4 DOD Ti sheet alloys indicated that Ti-4Al3Mo-1V and Ti-6Al-4V had about equal resistance to penetration by interstitial contaminants. The hardness penetration tests showed Ti-13V11Cr-3Al and Ti-2.5Al-16V alloys had lower resistance to contamination in that order. The Ti-5Al-2.5Sn, Ti-6Al-4V, and Ti-13V-11Cr-3Al alloys were evaluated for susceptibility to H embrittlement induced by chemically milling in a hydrofluoric acid bath. The all-alpha Ti-5Al2.5Sn alloy was not embrittled. The Ti-6Al-4V alloy was only slightly embrittled, while the Ti-13V-11Cr-3Al alloy was severely embrittled. An investigation concerning the titanium-LOX reaction was conducted by using high-pressure gaseous O. The study established that a fresh Ti surface would react with gaseous O under about 100-psig pressure between -250 F and room temperature. Several methods of producing flat solution-treated titanium alloy sheet are reviewed and a new concept is described. Basically, the new method involves heating and cooling the sheet under tension.