Unexpected nanoscale phase separation in sputter-deposited Ni-25 at.% Al thin films

作者：Banerjee R^*; Thompson GB; Viswanathan GB; Fraser HL

来源：Philosophical Magazine Letters, 2002, 82(11): 623-633.

DOI：10.1080/0950083021000036076

Thin films of nominal composition Ni-25 at.% Al, sputter deposited from a target of the intermetallic compound Ni3Al on unheated substrates, exhibit an unexpected phase separation, in contrast with other intermetallic-forming systems such as Ti-Al which are deposited as compositionally homogeneous amorphous films under similar conditions. Precipitates of a novel tetragonal phase, a few nanometres in size, were formed in the matrix consisting of a fcc Ni-rich Ni(Al) phase and a hcp Ni-rich Ni(Al) phase. Ni Al films of the same composition deposited on heated substrates exhibited the formation of a single, chemically long-range-ordered Ni3Al phase with the L1(2) structure, the thermodynamically stable phase for this composition.

• 出版日期2002-11