MICROSTRUCTURE AND MECHANICAL-PROPERTIES OF A PM TIAL-W ALLOY PROCESSED BY HOT ISOSTATIC PRESSING

PM Ti-48at.%Al-2at.%W alloy was fully consolidated under two Mp condit ions. A HIP cycle with a peak temperature of 1360 degrees C produced a fine-grained duplex microstructure. Increasing the peak temperature t o 1395 degrees C developed a coarse-grained fully lamellar microstruct ure. The former yielded better room-temperature tensile strength and d uctility, while the latter showed slightly higher ultimate tensile str ength at 850 degrees C and superior creep resistance at 760 degrees C, 276 MPa. The fracture surfaces and deformation substructures of the t ested specimens were analyzed and correlated with their mechanical beh aviour. The effect of HIP conditions on the microstructures and the mi crostructure-property relationships is discussed.