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1. Application of soft magnetic of amorphous alloys Nguyen Hoang Viet Nano-Particulate Materials Processing (NPMP)

3. Amorphous configuration exhibits unique properties such as h igh strength, large elastic limit, excellent wear & corrosion resistance… Terms: Amorphous Alloys, (Bulk) Metallic glasses, Inorganic Amorphous Materials,… Crystalline Structure Amorphous Structure Properties of Metallic Glasses High strength & elasticity of BMGs Potential for structural application High strength of Ti- based BMGs ~ 2200MPa Adapted from http:// www.nanonet.go.jp/english/mailmag/2004/014a.html Characteristics of Metallic Glass

4. Diffraction pattern (TEM) Complete amorphization after 20h of MA Ti 50 Cu 25 Ni 20 Sn 5 amorphous alloy by MA Amorphous Structure Charactezations DSC analysis Glass transition Temp. Crystallization Temperature After Oanh NH et. al. NPMP LAB [3] .

6. Preparation [5] *: rapid quenching method **: sintering – SPS, hot press, hot extrusion,… Mold casting, consolidation of amor. powder and ribbon ** . Bulk Water-in quenching technique * Wire Planar flow (tape) casting * or melt spinning Ribbon Mechanical alloying, atomization * , electrodeposition Powder Method Form

7. Relationship between permeability,  e (at 1 kHz) and saturation polarization for soft magnetic materials (adapted from Ref. [193] [4] ). Isotropic magnetic properties? Stress – differences in cooling rates through thickness of ribbons => Anisotropy Thermal annealing – removal of internal stresses => Mitigating the Anisotropy Fig.: The Nd 60 Fe 10 Co 20 Al 10 alloys prepared by splat quenching, melt spinning, and mold casting. Primary crystallization of amorphous precursors => very fine nanocrystalline grain size in amorphous matrix

8. Designing and developing a nanocrystalline soft magnetic material from an amorphous precursor route [5-Michael E. McHenry et. al. ]

16. Many Thanks for your attention!