The tensile and fracture toughness properties of prealloyed (PA) material are at levels at least equivalent to wrought product (Table 8.11) [18, 19], and with adequate precautions to avoid contamination of the powder S-N fatigue behavior is also at least at ingot levels. And as with BE product, S-N fatigue can be further improved by use of innovative heat treatments or THP.

Rapidly solidified (RS) titanium alloys containing rare-earth additions show some improvements in creep behavior [19] but have not yet seen commercial use. The RS approach can also be used to produce high-strength alloys such as the normally segregation prone Ti-1Al-8V-5Fe [19]. Little advantage has been achieved for the intermetallics using RS; with the caveat that the near-net-shape processing may offer an advantage for the very difficult to fabricate y compositions.

Development of mechanically alloyed (MA) titanium alloys is at a very early stage with virtually no mechanical properties available [19]. Early indications, however, suggest that improved dispersions of second-phase particles and enhanced strength-ductility combinations may occur, the latter in very fine grained nanostructured material.

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