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Manufacturing of Metallic Emulsions. István BUDAI Ph.D. University of Derbecen Hun ga ry. ISCAME 10-11. october 2013. Hun ga ry. Motivation and theoretical basic. Research goal: opening a principally new route to produce thick wall monotectic alloys.
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Manufacturing of Metallic Emulsions István BUDAI Ph.D. University of Derbecen Hungary ISCAME 10-11. october 2013.Hungary
Motivation and theoreticalbasic Research goal:opening a principally new route to produce thick wallmonotectic alloys EMULSION: is a mixture of two or more liquids which are normally immiscible (un-blendable). Emulsions are part of a more general class of two-phase systems of matter called colloids. Although the terms colloid and emulsion are sometimes used interchangeably, emulsion is used when both the dispersed and the continuous phase are liquid. In an emulsion, one liquid (the dispersed phase) is dispersed in the other (the continuous phase) MONOTECTIC alloy: An isothermal reversible reaction in a binary system, in which a liquid, on cooling, decomposes into a second liquid of a different composition and a solid. István BUDAI:Manufacturing of Metallic Emulsions
Production of monotectic alloys • powder metallurgy (high pressure, grinding cost) • strip casting (high cooling and crystallization rate) • plannar flow casting (high cooling rate) • microgravity (high cost) • laser technology (high cost) • emulsificaton technology István BUDAI:Manufacturing of Metallic Emulsions
Emulsification tensid Instabil droplet Stabilized droplet Solid particle polymer Stabilized droplet Pickering emulsions István BUDAI:Manufacturing of Metallic Emulsions
Pickering emulsion water particle oil oil water water István BUDAI:Manufacturing of Metallic Emulsions
Method István BUDAI:Manufacturing of Metallic Emulsions
Experimental setup baffles István BUDAI:Manufacturing of Metallic Emulsions
Experimentalmethod • The weighed specimens of one of the Al-matrixcomposites and the second phase (Bi, or Cd or Pb) wereplaced into the crucible. • The crucible was kept open,but the constant flow of argon gas with the flow rate of1 l/min was blown on the surface of the metal to preventsevere oxidation. • The crucible was heated with theheating rate of 350 °C/h until the final temperature of700 °C. • The system was kept at this temperature during1 hour. Then, themixer wasintroduced and the system wasfirst mixed with the rotational speed of 50 rotation/minduring 20 minutes. After that, the emulsification tookplace with the rotational speed of 1000 rotation/minduring 5 minutes. • After this, the mixer was switched offand taken out of the crucible. The crucible was taken outof the furnace and was spontaneouslycooled in air.
Materials • A356 + 25,2 v/v % Bi (without particles) • MMC1 (Al-Si(7) + 20 v/v % SiCp) + 24,7 v/v % Bi • MMC1 (Al-Si(7) + 30 v/v % SiCp) + 47 v/v % Bi • MMC1 (Al-Si(7)+ 20 v/v % SiCp) + 24, 60, 70 v/v % Cd • MMC1 (Al-Si(7) + 20 v/v % SiCp) + 25 and 67 v/v % Pb • MMC2 (Al + 5,2 v/v % Al2O3p) + 6,8 v/v % Bi • MMC2 (Al + 5,2 v/v % Al2O3p) + 7,4 v/v % Cd • MMC3 (Al + Sr(10) + Ti(1) + B(0,2)) +6,5 v/v %Bi • MMC3 (Al + Sr(10) + Ti(1)+ B(0,2)) + 7,2 v/v % Cd • MMC3 (Al + Sr(10) + Ti(1)+ B(0,2)) + 7,2 and 14,6 v/v %Pb
Microstructure1. MMC1 (Al-Si(7) + 20 v/v % SiC) + 24,7 v/v % Bi
Microstructure 2. -phase inversion- MMC1 (Al-Si(7) + 30 v/v % SiC) + 47 v/v % Bi
Microstructure 3. MMC3 (Al + Sr(10) + Ti(1)+ B(0,2)) + 7,2 v/v % Cd
Limit of this technology • to long mixing time: 25 min. • limited experimental rotate max: 1600 1/min coalesce, sedimentation Bottom of experimental product
New mixer - disperser • mixing time: 30 sec. • experimental rotate: 10000 1/min István BUDAI:Manufacturing of Metallic Emulsions
Microstructure MMC3 (Al + Sr(10) + Ti(1)+ B(0,2)) + 7,2 v/v % Cd Bottom of experimental product István BUDAI:Manufacturing of Metallic Emulsions
Summary / conclusion / future • Particle-stabilized liquidmetallic emulsions can be produced under the sameconditions (contact angle and liquid-phase ratio), ascommonly known for particle-stabilized oil/water emulsions.Upon solidification, these emulsions becomeparticle-stabilized monotectic alloys with homogeneouslydistributed second phase at least in a part ofthe ingot. Thus, stabilizing particles can open a principallynew production route of monotectic alloys • In colloid chemistry, it is known that when reducingthe size of the stabilizing particles, the size of theemulsion droplets can be reduced. • To produce Al-matrix composite with submicron particles • To investigate the mechnical properties István BUDAI:Manufacturing of Metallic Emulsions
Relevant papers United States Patent US 2011/0185855 A1, Aug. 4. 2011: Method to produce monotecticdisperesed metallic alloys (GyörgyKaptay, IstvánBudai) I. Budai, O. Z. Nagy, G. Kaptay: Inversion of a liquidBi/AlmetallicemulsionstabilizedbysolidSiCparticles, Coll Surf A, 2011, vol.377, pp. 325–329 (2010 IF = 1.988) I. Budai, G. Kaptay: MonotecticAl/Cd alloyswithhomogeneouslydispersedCd-dropletsstabilizedbystrontiumaluminideprecipitates, INTERMETALLICS, 2011, vol.19, pp. 423-425 (2010 IF = 2.231) I. Budai, G. Kaptay: Wettability of SiC and alumina particles by liquid Bi under liquid Al,J Mater Sci, 2010 vol. 45, pp. 2090–2098 (2009 IF = 1.471) I. Budai, G. Kaptay: A new class of engineering materials: particles stabilized metallic emulsions and monotectic alloys, Metall. Mater Trans A, 2009 vol.40A, pp.1524-1528. (IF = 1.564)
Thank You for your attention! "This research was realized in the frames of TÁMOP 4.2.4. A/2-11-1-2012-0001 "National Excellence Program - Elaborating and operating an inland student and researcher personal support system convergence program" The project was subsidized by the European Union and co-financed by the European Social Fund „