Al-based metallic glass composites containing fcc Pb-rich crystalline spheres

Liquid immiscible systems present a unique opportunity in designing composites with sphere- dispersed microstructure. The authors report here phase formation of a multicomponent Al(82.87)Pb(2.5)Ni(4.88)Y(7.8)Co(1.95) alloy upon melt spinning. The alloy undergoes liquid- liquid phase transformation in the liquid immiscibility gap and subsequently solidifies into Pb- rich crystalline phase and Al- rich amorphous phase. The Pb- rich phase with sphere shape is dispersed in the Al- based metallic glass matrix. The average diameter of the Pb- rich spheres is similar to 0.62 mu m near the free side and similar to 0.03 mu m near the wheel side of the ribbon. (C) 2008 American Institute of Physics.

[1]  Jiu-zhou Zhao,et al.  Directional Solidification and Microstructural Refinement of Immiscible Alloys , 2008 .

[2]  Douglas C. Hofmann,et al.  Designing metallic glass matrix composites with high toughness and tensile ductility , 2008, Nature.

[3]  Lorenz Ratke,et al.  Solidification microstructure and dynamics of metastable phase transformation in undercooled liquid Cu–Fe alloys , 2006 .

[4]  A. Yavari,et al.  Cobalt-based bulk glassy alloy with ultrahigh strength and soft magnetic properties , 2003, Nature materials.

[5]  U. Kühn,et al.  ZrNbCuNiAl bulk metallic glass matrix composites containing dendritic bcc phase precipitates , 2002 .

[6]  A. Inoue,et al.  Ductility of bulk nanocrystalline composites and metallic glasses at room temperature , 2000 .

[7]  Hays,et al.  Microstructure controlled shear band pattern formation and enhanced plasticity of bulk metallic glasses containing in situ formed ductile phase dendrite dispersions , 2000, Physical review letters.

[8]  W. Johnson,et al.  Melt infiltration casting of bulk metallic-glass matrix composites , 1998 .

[9]  J. Zhao,et al.  Repeated Nucleation of Minority Phase Droplets Induced by Drop Motion , 1998 .

[10]  K. L. Lee,et al.  Metastable liquid phase separation in undercooled molten Pd_40.5Ni_40.5P_19 , 1997 .

[11]  Hajime Tanaka.  Coarsening mechanisms of droplet spinodal decomposition in binary fluid mixtures , 1996 .

[12]  L. Ratke,et al.  Liquid immiscible alloys , 1995 .

[13]  S. Kumai,et al.  Solidification structure of monotectic alloys , 1991 .

[14]  I. Lifshitz,et al.  The kinetics of precipitation from supersaturated solid solutions , 1961 .