Structure and transformation behavior of a rapidly solidified Al6.4wt.%Hf alloy

Abstract

An Al6.4wt.%Hf alloy was rapidly solidified from the liquid state using the melt-spinning technique. Transmission electron microscopy and diffraction techniques have been extensively employed to characterize the metastable and stable phases produced in the as-quenched condition and those obtained on subsequent thermal annealing. In the as-quenched state, the alloy showed the presence of only a supersaturated solid solution. On annealing the foils, the formation of a metastable cubic ordered phase Al3Hf was observed. This discontinuous precipitate transformed to the equilibrium phases on annealing at temperatures higher than 773 K.