Abstract: Method and apparatus for making metallic powder particles wherein a metallic melt is atomized by a rotating disk or other atomizer at an atomizing location in a manner to form molten droplets moving in a direction away from said atomizing location. The atomized droplets pass through a series of thin liquid quenching sheets disposed in succession about the atomizing location with each successive quenching sheet being at an increasing distance from the atomizing location. The atomized droplets are incrementally cooled and optionally passivated as they pass through the series of liquid quenching sheets without distorting the atomized droplets from their generally spherical shape. The atomized, cooled droplets can be received in a chamber having a collection wall disposed outwardly of the series of liquid quenching sheets.
Type:
Grant
Filed:
November 20, 1995
Date of Patent:
April 14, 1998
Assignee:
Iowa State University Research Foundation, Inc.
Inventors:
Iver E. Anderson, Matthew G. Osborne, Robert L. Terpstra
Abstract: Solid spheres of substantially uniform size and shape and coated with a lower temperature melting material are formed for use in interconnect arrays, solder pastes, Z-axis conduction adhesives, etc. Drops of two materials are merged in flight forming a coating of the lower melting temperature material on the drop of higher melting temperature material.
Abstract: An encapsulated asphalt prill having an impervious, water-insoluble shell, and a process for making same are disclosed. The encapsulating material are preferably composed primarily of materials such as molten fatty acids, low melt polymers, waxes, elastomers (synthetic rubbers) or plastomers many of which are also used as blending agents to enhance the final use properties of the commercial asphalt end products.
Abstract: Apparatus and method for making powder from a metallic melt by atomizing the melt to form droplets and reacting the droplets downstream of the atomizing location with a reactive gas. The droplets are reacted with the gas at a temperature where a solidified exterior surface is formed thereon and where a protective refractory barrier layer (reaction layer) is formed whose penetration into the droplets is limited by the presence of the solidified surface so as to avoid selective reduction of key reactive alloyants needed to achieve desired powder end use properties. The barrier layer protects the reactive powder particles from environmental constituents such as air and water in the liquid or vapor form during subsequent fabrication of the powder to end-use shapes and during use in the intended service environment.
Type:
Grant
Filed:
October 24, 1994
Date of Patent:
December 31, 1996
Assignee:
Iowa State University Research Foundation, Inc.
Inventors:
Iver E. Anderson, Barbara K. Lograsso, Robert L. Terpstra
Abstract: A process of producing granules of a reactive metal. The process comprises providing a source of molten reactive metal, forming discrete droplets of the molten metal, contacting the droplets while still substantially molten with a fluidized bed of particles maintained at a temperature substantially below the solidus temperature of the metal and freezing the droplets as discrete granules of the reactive metal in the fluidized bed. The invention also provides apparatus for carrying out the method and product produced by the method, including a magnesium-containing additive for aluminum alloying. The use of a fluidized bed for cooling and freezing the droplets avoids problems encountered in prior methods and also makes it possible to provide coatings of various kinds on the surfaces of the granules, if desired.
Type:
Grant
Filed:
November 29, 1994
Date of Patent:
August 27, 1996
Assignee:
Alcan International Limited
Inventors:
Ghyslain Dube, Claude Dupuis, Joseph Langlais, Serge Lavoie, Stephane Rompre, Sylvain Trottier, Gilles Turcotte
Abstract: A method of synthesizing encapsulated nanocrystals inside protective shells is disclosed. This method produces nanocrystals of metals, alloys, and compounds which are individually encapsulated by protective graphite shells which completely separate the nanocrystals from the environment. A separation method is also disclosed which eliminates most of all other debris except the encapsulated nanocrystals from the preparation product.
Type:
Grant
Filed:
October 27, 1994
Date of Patent:
December 5, 1995
Assignee:
Northwestern University
Inventors:
Vinayak P. Dravid, Mao-Hua Teng, Jonathon J. Host, Brian R. Elliott, D. Lynn Johnson, Thomas O. Mason, Julia R. Weertman, J.-H. Hwang
Abstract: A moly permalloy powder core (MPP core) to be used in SMPS (switching mode power supply) and DC converters is disclosed. Particularly, a process for manufacturing an MPP core forming powder and a process for manufacturing the MPP core using the MPP core forming powder are disclosed, in which the MPP core forming powder can be directly manufactured from melts. The process for manufacturing a powder for an MPP core (moly permalloy powder core) includes the steps of: melting an alloy composed of, in wt %, 1.6-4.0% of Mo, 78-83% of Ni, and the balance of Fe; and manufacturing a powder by spouting a fluid into the flow of the melts. As the Mpp core forming material is manufactured directly from the melts, the workability and productivity are improved, and the yield and the forming density can be also improved, as well as improving the frequency characteristics of the MPP core.
Abstract: Apparatus and method for making powder from a metallic melt by atomizing the melt to form droplets and reacting the droplets downstream of the atomizing location with a reactive gas. The droplets are reacted with the gas at a temperature where a solidified exterior surface is formed thereon and where a protective refractory barrier layer (reaction layer) is formed whose penetration into the droplets is limited by the presence of the solidified surface so as to avoid selective reduction of key reactive alloyants needed to achieve desired powder end use properties. The barrier layer protects the reactive powder particles from environmental constituents such as air and water in the liquid or vapor form during subsequent fabrication of the powder to end-use shapes and during use in the intended service environment.
Type:
Grant
Filed:
August 5, 1992
Date of Patent:
December 13, 1994
Assignee:
Iowa State University Research Foundation, Inc.
Inventors:
Iver E. Anderson, Barbara K. Lograsso, Robert L. Terpstra
Abstract: A method for making an isotropic permanent magnet comprises atomizing a melt of a rare earth-transition metal alloy (e.g., an Nd--Fe--B alloy enriched in Nd and B) under conditions to produce protectively coated, rapidly solidified, generally spherical alloy particles wherein a majority of the particles are produced/size classified within a given size fraction (e.g., 5 to 40 microns diameter) exhibiting optimum as-atomized magnetic properties and subjecting the particles to concurrent elevated temperature and elevated isotropic pressure for a time effective to yield a densified, magnetically isotropic magnet compact having enhanced magnetic properties and mechanical properties.
Type:
Grant
Filed:
April 15, 1992
Date of Patent:
September 7, 1993
Assignee:
Iowa State University Research Foundation, Inc.
Inventors:
R. William McCallum, Kevin W. Dennis, Barbara K. Lograsso, Iver E. Anderson