Massachusetts Institute of Technology

Norton Company

Leach & Garner Company

Infinium, Inc.

Codman & Shurtleff, Inc.

Thomas W Eagar

Sergej-Tomislav V Buljan

Bradley J Miller

Eric A Barringer

Ren-Kae Shiue

Dwarika P Agarwal

Adam Clayton Powell, Iv

Soobhankar Pati

Laura L Bourguignon

Jason Douglas

Rosaire Marcotte

Luciano Spiridigliozzi

Michael Buchman

Richard M Andrews

Rene J Cabrera

Stephen Joseph Derezinski

Eric R Schulz

Gregory J Dunn

Charly Allemand

Mansoor A Khan

Christopher S Musso

Joseph G Kaiser

Stephen J Derezinski, Iii

Rene Jopson Cabrera

Methods for condensing metal vapors comprising directing a mixture of metal vapor and carrier gas into at least one inlet conduit are provided. Some methods comprise directing the mixture of metal vapor and carrier gas into a holding tank for liquid metal and subsequently into at least one outlet conduit operatively connected to the tank; cooling the at least one outlet conduit to cause some of the metal vapor inside the conduit to condense to solid metal; subsequent to condensing solid metal, stopping the cooling of at least one of the outlet conduits and commencing heating of the same outlet conduits to cause the solid metal to melt to form liquid metal; collecting the liquid metal in the tank; and preventing the remaining metal vapor and carrier gas from exiting the same outlet conduits during at least a portion of the heating of the same outlet conduits.

Apparatus and method for condensing metal vapor

An apparatus for condensing metal vapors has at least one inlet conduit that is cooled to cause a portion of the metal vapor to condense to liquid. The apparatus also has a holding tank that is connected to the inlet conduit that collects condensed liquid metal. The apparatus also has at least one outlet conduit connected to the holding tank that is cooled to cause a portion of the remaining metal vapor to condense to solid metal. The apparatus also has at least one heater that heats the at least one outlet conduit to cause the solid metal to melt to liquid metal and subsequently flow in to the holding tank. The apparatus also has at least one sealing mechanism located at a distal end of the at least one outlet conduit for preventing metal vapor and carrier gas from exiting the outlet conduit during heating of the outlet conduit.

Channeled articles having very small diameter channels spaced very closely can be made by packing elongated cores in a fixture, clamping them, and then introducing matrix material around the cores. The matrix material is formed into a unitary body and solidified. The cores are pulled out, leaving open channels where they had been. Some core and matrix combinations will permit the cores to be pulled out. Others require a core release coating to be applied to the cores. The cores can be metal or ceramic or polymer, and the matrix can be metal or ceramic or polymer. The cores can be solid, or hollow. Rather than pulling the cores out, if they are polymer, they can be burned out. The matrix can be formed by liquid state, solid state, or hybrid liquid/solid state techniques. A related technique uses hollow cores, which are not pulled out, but which remain in the body after unification. For such tube-walled articles, the matrix can be formed similarly. Rather than insuring core release, core retention is required. Such may occur due to the nature of the materials, or a specific core retention coating may be provided. Articles made of such material include heat sinks for semiconductor devices, light-weight structural components, thermally activated actuators, etc. Very small channel diameters and very large length to opening aspect ratios can be achieved. Heat exchange fluid can be compressed and pumped through such an article at very high efficiencies, to cool semiconductor devices.

Methods for forming articles having very small channels therethrough, and such articles, and methods of using such articles

A bond for a metal single layer abrasive tool can be easily chemically and electrochemically stripped from the metal core of a recovered used tool to facilitate reuse of the core. Relative to conventionally bonded tools, the speed of stripping the novel bond is quick, and the stripped core has a smooth, clean surface which needs only minimal mechanical repair prior to reuse. The composition of the novel bond consists essentially of copper, tin and titanium. It can be brazed at temperatures below diamond graphitization and is chemically compatible with diamond. Hence, the bond is particularly useful for the manufacture of large diameter, superabrasive metal single layer abrasive wheels employed in the construction industry. The bond can be applied to the cutting surface of the abrasive tool as a uniform mixture of bronze alloy, titanium compound and copper powders. The powders may be mixed with a liquid vehicle and applied as a paste. The method of brazing the bond incorporates heating the bond composition to a temperature at most about 880&deg; C. to melt the bronze alloy and titanium compound components, and raising the temperature to at least about 900&deg; C. to dissolve the copper. The bond can also include an about 10-200 &mgr;m thick barrier layer of copper coating the cutting surface between the core and the bond composition.

Removable bond for abrasive tool

An abrasive grit for a metal bonded Single Layer abrasive tool includes abrasive grains coated with a first active component. The active component is mechanically-bound to the surface of the superabrasive grains. Preferably the abrasive is a superabrasive, especially diamond, and the first active component is titanium, either in the form of elemental Ti or TiH.sub.2. The novel grit is made by mixing the first active powder component in a liquid binder to form an adhesive paste; mixing the paste with the abrasive grains to wet the grains, and drying the mixture to adhere active component to the grains. The coated abrasive can be brazed onto a core to form a Single Layer tool, especially with a brazing composition that includes a bronze alloy and small concentrations of a second active component. During brazing the novel abrasive grains provide excellent surface contact with the brazing composition and the braze strongly bind the grains to the tool core. The brazed composition is easy to chemically or electrochemically strip from the cores of worn abrasive tools to permit reconstruction of the tools.

Abrasive tool containing coated superabrasive grain

A bond material for a metal single layer abrasive tool, and especially for a tool with diamond abrasive, provides an excellent combination of mechanical properties including structural strength and impact resistance. The bond material is sufficiently compatible with both metal and diamond to effectively wet the abrasive grains and the core of the tool during brazing. The bond material can braze at a temperature range low enough that the core will not distort and diamond grains will not graphitize during brazing. The novel bond material composition contains a copper/tin bronze alloy; elemental titanium; zirconium; hard granular wear resistant particles; and elemental carbon. The wear resistant particles are preferably titanium carbide. Importantly, the bond produced from the material has superior wear resistance while remaining very adhesive to diamond.

Wear resistant bond for an abrasive tool

An apparatus and method for non-contact temperature measurement of an object, using least-squares-based multiwavelength pyrometry techniques. Radiances from an object are detected by a spectrograph/detector apparatus and are converted into electronic signals readable by a computer. The computer then operates on these signals as data to be curve-fit, using least squares analysis, to a predetermined theoretical function for the dependence of the radiance on the wavelength. When the computer has minimized the least-squares difference function, the computer identified a parameter representing the temperature and reports this value to the user, along with a collaterally calculated maximum error in the temperature estimate.

Emissivity independent multiwavelength pyrometer

A unique hardenable silver alloy is provided which is solution annealed and preferably age-hardened to yield a silver alloy of exceptional and reversible hardness. The alloys utilize intermetallic systems comprising; silver, copper, combined with lithium alone or tin alone in varying percent amounts, or silver, copper, lithium and either tin or antimony, or silver, copper, lithium, tin and antimony, or silver, copper, lithium, tin and bismuth, or silver, copper, lithium, tin, bismuth and antimony.

Silver alloys of exceptional and reversible hardness

A unique hardenable silver alloy is provided which is solution annealed and preferably age-hardened to yield a silver alloy of exceptional and reversible hardness. The alloys utilize intermetallic systems comprising silver, copper, combined with lithium alone or tin alone in varying percent amounts, or silver, copper, lithium and either tin or antimony, or silver, copper, lithium and either aluminum or indium or zinc, or silver, copper, antiomony and either aluminum or indium or zinc, or silver, copper, lithium, tin and antimony, or silver, copper, lithium, tin and bismuth, or silver, copper, lithium, tin, bismuth and antimony.

A welding flux binder and welding flux comprising the reaction product of a hydrolyzed and polymerized organometallic compound selected from the group consisting of metal alkoxides including tetraalkylorthosilicate, tetraalkylorthotitanate, tetraalkylorthozirconate and trialkylaluminate, metal esters, and metal oxalates. The organometallic compound is hydrolyzed and then polymerized to form a gel glass phase. Alkali and alkaline earth salts are added to stabilize and reduce the viscosity of the gel. The resulting welding flux binder and flux are non-hygroscopic and have a high fired strength.

Non-hygroscopic welding flux binders

A surgical tool for intercepting laser energy after it has energized a target site but before it energizes adjacent tissue. The instrument includes substrate of material having a high thermal conductivity for transmitting laser energy away from the surgical site and a highly absorbent surface material for absorbing radiant energy at the wavelength of the incident laser.

Laser instrument

A welding flux binder is provided which comprises an alkali-alkaline earth silicate hydrolyzed and polymerized from tetraalkylorthosilicate, Si(OR).sub.4, wherein R is --CH.sub.3, --C.sub.2 H.sub.5, or --C.sub.3 H.sub.7, and alkali and alkaline earth salts. The reaction product of the tetraalkylorthosilicate and metal salts, M.sub.2 O.M'O.SiO.sub.2, where M is potassium, sodium or lithium, and M' is magnesium, calcium or barium, has several advantages as a welding flux binder. For example, it is not hygroscopic and can be prepared at low temperatures since the alkali ions lower the melting point for viscous sintering of the gel phase. Because of the low temperature processing, a wide variety of solid additives with low thermal stability, such as some metals, carbonates, and fluorides, can be incorporated into the flux. Other dopants may also be readily incorporated into the binder during the gel phase.

After measuring the bulk resistance the surface of high strength low alloy steel material is treated to form a high resistance coating on its surface. When resistance welding the material the coating permits weld formation without significant expulsion or excessive electrode force over a wide range of operating conditions.

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Belmont, MA, United States of America

Thomas W Eagar