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Most Cited Journal Articles 2004-Materials Science
Following is a CAS database record representing a highly cited journal article.
CAPLUS COPYRIGHT 2005 ACS on STN
A review with 80 refs. Bulk metallic materials have ordinarily been produced by melting and solidification processes for the last several thousand years. However, metallic liq. is unstable at temps. below the melting temp. and solidifies immediately into cryst. phases. Consequently, all bulk engineering alloys are composed of a cryst. structure. Recently, this common concept was exploded by the findings of the stabilization phenomenon of the supercooled liq. for a no. of alloys in the Mg-, lanthanide-, Zr-, Ti-, Fe-, Co-, Pd-Cu- and Ni-based systems. The alloys with the stabilized supercooled liq. state have three features in their alloy components, i.e. multicomponent systems, significant at. size ratios above 12%, and neg. heats of mixing. The stabilization mechanism was investigated from exptl. data of structure analyses and fundamental phys. properties. The stabilization has enabled the prodn. of bulk amorphous alloys in the thickness range of 1-100 mm by using various casting processes. Bulk amorphous Zr-based alloys exhibit high mech. strength, high fracture toughness and good corrosion resistance and were used for sporting goods materials. The stabilization also leads to the appearance of a large supercooled liq. region before crystn. and enables high-strain rate superplasticity through Newtonian flow. The new Fe- and Co-based amorphous alloys exhibit a large supercooled liq. region and good soft magnetic properties which are characterized by low coercive force and high permeability. Furthermore, homogeneous dispersion of nanoscale particles into Zr-based bulk amorphous alloys was found to cause an improvement of tensile strength without detriment to good ductility. The discovery of the stabilization phenomenon, followed by the clarification of the stabilization criteria of the supercooled liq., will promise the future definite development of bulk amorphous alloys as new basic science and engineering materials.
Updated 5/1/2007 9:35:42 AM
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