TENSION AND COMPRESSION TESTING OF SINGLE-CRYSTALLINE GAMMA-TI-55.5 PCT AL

High-quality single crystals 6 to 10 mm in diameter of gamma-Ti 55.5 p et Al have been grown using the optical float zone furnace technique. These crystals have been oriented and cut into microsample tension and compression specimens with a gage area of 250 x 250 mu m and an effec tive gage length of 300 mu m. These specimens have been deformed using a microsample testing machine which applies loads on the order of 50 N and measures strain using an interferometric strain/displacement gag e. Stress-strain curves have been obtained for four different orientat ions and two temperatures and as a function of the sense of the applie d load. Of special interest is the availability of tensile data for th e resolved shear stress. Preliminary comparison of tension and compres sion microsample tests indicates that the tension-compression asymmetr y is negligible at 500 K.