Abstract
The composition and/or temperature dependence of the dynamic Young's modulus for the ordered B2 Co-Al, Fe-Al, and Ni-Al aluminides has been investigated using the piezoelectric ultrasonic composite oscillator technique (PUCOT). The modulus has been measured in the composition interval 48.49 to 52.28 atomic % Co, 50.87 to 60.2 atomic % Fe, and 49.22 to 55.95 atomic % Ni for Co-Al, Fe-Al, and Ni-Al, respectively. The measured values for Co-Al are in the temperature interval 300 to 1300 K, while those for the other systems are for ambient temperature only. The data points show that Co-Al is stiffer than Fe-Al, which is stiffer than Ni-Al. The values reported herein for Co-Al are the first of their kind, since none has been reported earlier. However, the data points for Fe-Al and Ni-Al are slightly higher than those reported in the literature.
