Sat, 26 Jul 2008 08:40:46 BST CiteULike: dchen alloy http://www.citeulike.org/user/dchen/tag/alloy CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/dchen/article/2751747 <i>Physical Review Letters, Vol. 99, No. 24. (2007)</i><br /><br />Foams with 55% and 76% open porosity were produced from a Ni-Mn-Ga magnetic shape-memory alloy by replication casting. These polycrystalline martensitic foams display a fully reversible magnetic-field-induced strain of up to 0.115% without bias stress, which is about 50 times larger than nonporous, fine-grained Ni-Mn-Ga. This very large improvement is attributed to the bamboolike structure of grains in the foam struts which, due to reduced internal constraints, deform by magnetic-field-induced twinning more easily than equiaxed grains in nonporous Ni-Mn-Ga. Increasing Magnetoplasticity in Polycrystalline Ni-Mn-Ga by Reducing Internal Constraints through Porosity Yuttanant Boonyongmaneerat Markus Chmielus David Dunand Peter Müllner doi:10.1103/PhysRevLett.99.247201 Physical Review Letters, Vol. 99, No. 24. (2007) 2008-05-04T00:05:33-00:00 2007 Physical Review Letters 99 24 APS 2007 alloy foam focus structure http://www.citeulike.org/user/dchen/article/2746714 <i>(1974)</i> MECHANISM FOR FLOW AND FRACTURE OF METALLIC GLASSES F Spaepen (1974) 2008-05-02T18:07:53-00:00 1974 alloy glass spaepen http://www.citeulike.org/user/dchen/article/2719221 <i>Applied Physics Letters, Vol. 73, No. 25. (1998), pp. 3665-3667.</i><br /><br />View This Record in Scopus Newtonian to non-Newtonian master flow curves of a bulk glass alloy Pd[sub 40]Ni[sub 10]Cu[sub 30]P[sub 20] Hidemi Kato Yoshihito Kawamura Akihisa Inoue HS Chen Applied Physics Letters, Vol. 73, No. 25. (1998), pp. 3665-3667. 2008-04-25T18:35:55-00:00 1998 Applied Physics Letters 73 25 3665 3667 AIP alloy elasticity shear http://www.citeulike.org/user/dchen/article/2678867 <i>Nature Materials 6, 192 - 197 (2007)</i><br /><br />A metal, or an alloy, can often exist in more than one crystal structure. The face-centred-cubic and body-centred-cubic forms of iron (or steel) are a familiar example of such polymorphism. When metallic materials are made in the amorphous form, is a parallel 'polyamorphism' possible? So far, polyamorphic phase transitions1, 2, 3, 4, 5, 6, 7 in the glassy state have been observed only in glasses involving directional and open (such as tetrahedral4, 5) coordination environments. Here, we report an in situX-ray diffraction observation of a pressure-induced transition between two distinct amorphous polymorphs in a Ce55Al45 metallic glass. The large density difference observed between the two polyamorphs is attributed to their different electronic and atomic structures, in particular the bond shortening revealed by ab initio modelling of the effects of f-electron delocalization8, 9, 10. This discovery offers a new perspective of the amorphous state of metals, and has implications for understanding the structure, evolution and properties of metallic glasses and related liquids. Our work also opens a new avenue towards technologically useful amorphous alloys that are compositionally identical but with different thermodynamic, functional and rheological properties11 due to different bonding and structural characteristics. Polyamorphism in a metallic glass Sheng1 Nature Materials 6, 192 - 197 (2007) 2008-04-16T20:10:00-00:00 Nature Materials 6, 192 - 197 (2007) alloy shear stz