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Publication numberUS2406172 A
Publication typeGrant
Publication dateAug 20, 1946
Filing dateMar 9, 1943
Priority dateFeb 7, 1942
Publication numberUS 2406172 A, US 2406172A, US-A-2406172, US2406172 A, US2406172A
InventorsSmithells Colin James
Original AssigneeBaker And Co Inc
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Platinum or allied metals, or their alloys, and articles made therefrom
US 2406172 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

Patented Aug. 20, 1946 PLATINUM OR ALLIED METALS, (SR THEIR ALLOYS, AND ARTICLES MADE THERE- FROM Colin James Smithells, Rugby, England, assignor, by mesne assignments, to Baker and Co. Inc.,

Newark, N. J.

No Drawing. Application Mai-ch 9, i943, Serial 1109122478552. In Great Britain February '7', g

6 Claims. (Cl. i 22) This invention relates to platinum, or any of the following allied metals in the platinum group, namely, rhodium, iridium, ruthenium, and palladium, and to alloys in which any of these metals forms the principal ingredient. The invention also relates to articles made from such metals or alloys and required to be able to withstand high temperatures and corrosive actions, such as sparking plug electrodes, thermocouples, electric furnace heating elements, and wire gauzes foruse as catalyst gauzes in chemical operations. to minimise the normal tendency of the initially fine-grained structure of such metals or their alloys to change into a coarse-grained structure when subjected to high temperatures with consequent deterioration of their mechanical properties.

The invention consists of a material, or an article made therefrom, in the form of a compacted and sintered agglomerate of platinum or any of the allied metals above specified or an alloy thereof, and refractory oxide, the constituents being initially in a finely divided condition.

For the production of materials consisting essentially of platinum, I may use commercially pure platinum, but preferably I use an alloy containing for example, about rhodium, or about 4% tungsten, or up to 30% iridium, or up to 30% ruthenium, the balance being platinum. The required finely divided condition is obtained by any known and suitable process such as precipitation, or decomposition and reduction in hydrogen, and the metal in this condition is intimately mixed with any suitable and finely divided oxide, such as alumina, thoria,

zirconia, lime, or oxides of the rare earths or alkaline earths, which are not easily reducible at the sintering temperature. Alternatively the refractory oxide, or compound adapted to produce it subsequently, is mixed with a compound of the metal (or compounds of the metals) before the reduction or decomposition. Thequantity of oxide required is usually from about 0.1% to 1% of the weight of the metal, and preferably about 0.25%. The best amount for any particular purpose is readily ascertainable by experiment. If too little is used there will be insuflicient control of grain growth; if too much is used the resulting metal will be difficult to shape by swaging, rolling or drawing. The mixture is then compacted by pressure, sintered, and subsequently swaged, rolled, drawn, or otherwise The object of the invention is rhodium, and thorium oxide.

treated to bring it to the form of a wire, or sheet 55 "is added an aqueous solution of rhodium ammonium chloride containing 10 grams of rhodium,

and an aqueous solution of thorium nitrate containing 0.5 gram of thorium oxide (ThOz). The resultant paste is evaporated to dryness with constant stirring to ensure a uniform distribution of the constituents. The dried mass is then heated in a current of hydrogen at about 850 C. to decompose the rhodium and the thorium salts,.leaving an intimate mixture of platinum, The product is sieved, packed into a steel mould and compressed under a pressure of about tons per square inch in order to form a coherent mass. The compressed material is then heated at about 1400-1550 C. in hydrogen for about one hour, the effect of this heating being to alloy the rhodium with the platinum, and to sinter the mass into a dense body, sufiiciently strong to enable it to be swaged, rolled, drawn, or otherwise treated to bring it to the form of a wire, sheet or any other desired condition.

In another example, I employ 96 grams of platinum dissolved in aqua regia, a solution of ammonium tungstate containing 4 grams of tungsten, and another or the same solution containing thorium nitrate having 0.2% grams of thorium oxide. The tungsten and thorium solutions are added to the platinum solution, and after neutralising with ammonia, the mixture is evaporated to dryness. The resulting powder is heated at about 800 C. in air and then heated to about 1000 C. in hydrogen. The product consisting of finely divided platinum, tungsten and thorium oxide is formed into a bar by pressing in a steel mould at about 50 tons per square inch. The bar is then sintered in hydrogen for about two hoursat about 1450 C. and finally swaged, rolled or drawn to the required form and dimensions.

Materials made in accordance with the invention are characterised by having a higher tensile strength and greater hardness than corresponding materials made in the usual way, and by a crystalline structure which is satisfactorily stable at high temperatures.

In the foregoing I have described the application of my invention to platinum or platinum alloys. But the invention is applicable in essentially the same way to the other allied metals already mentioned, namely, rhodium, iridium, ruthenium, and palladium.

The platinum, and platinum alloys produced in accordance with my invention are especially useful for use as sparking plug electrodes. They are also useful for thermo-couples, furnace heating elements, catalyst gauzes, and other articles required to resist high temperatures (of the order of 1000" C. or more), or corrosive actions under which metals produced in ordinary ways are liable to coarsening of the grain structure or other deterioration resulting in weakening such mechanical properties as strength or hardness.

As regards materials produced from any of the other allied metals mentioned or alloys in which these metals form the principal ingredients I am unable on the basis of my present experience to specify any purpose for which they are especially useful, but such metals or their alloys, also possess the same property as the platinum materials above described, in that their grain size is satisfactorily stable at high temperatures, and.

therefore they may be applicable to a variety of uses in which this property serves a useful purpose.

In the foregoing I have given examples which enable anyone skilled in the art to produce materials in accordance with the invention, but I wish it to be understood that my invention is not limited to those examples, as the relative proportions of the ingredients, the nature of the metals to be alloyed with the principal metal, the nature of the oxides used, the temperatures employed for heating the substances, and the mode of bringing the ingredients to the finely divided condition may be varied, provided always that the end product consists of the desired comacted, sintered a l merat As regards the pressures to which the ingredients are subjected,

these may vary over a wide range, as for example from 5-50 tons per square inch, the most appropriate pressure being dependent on the metal or alloy and the fineness of the powder, in all cases it being advantageous to make the compressed mass as dense as possible.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

l. A material in the form of a compacted and sintered agglomerate of a metal chosen from the group consisting of platinum, rhodium, iridium, ruthenium, palladium and alloys of these metals, and a refractory oxide, the constituents being initially in a finely divided condition.

2. A material in the form of a compacted and sintered agglomerate of platinum alloyed with a metal chosen from the group consisting of rhodium, tungsten, iridium nd ruthenium, in the approximate proportions specified, and a refractory oxide, both being initially in a finely divided condition, and the proportion of oxide being from about 0.1% to 1.0% of the weight of the metal. v

3. A material as claimed in claim 2, in which the oxide consists of thorium oxide.

4. A material as claimed in claim 2, which contains platinum alloyed with about 10% of rhodium, and about 0.5% of thorium oxide.

5. A material as claimed in claim 2, which contains platinum alloyed with about 4% of tungsten, and about 0.2% of thorium oxide.

6. Sparking plug electrodes, thermo-couples, electric furnace heating elements, catalyst gauzes, or like articles required to resist high temperatures or corrosive chemical actions, and

. made from a compacted and sintered agglomerate as claimed in claim 1 and containing platinum as the principal ingredient.


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2467446 *Oct 25, 1945Apr 19, 1949Baker & Co IncCatalytic oxidation of ammonia to oxides of nitrogen
US2476208 *Oct 26, 1944Jul 12, 1949Int Nickel CoSintered precious metal product
US2476222 *Feb 7, 1945Jul 12, 1949Int Nickel CoProduction of powdered metal mixtures for sintering
US2506414 *Dec 5, 1947May 2, 1950Bell Telephone Labor IncSealed wire contact device
US2537733 *May 1, 1950Jan 9, 1951Adolph CohnVariable resistor
US2545438 *Jan 12, 1949Mar 20, 1951Baker & Co IncSpark plug electrode
US2636819 *Jan 31, 1951Apr 28, 1953Baker & Co IncGrain stabilizing metals and alloys
US2641582 *Oct 3, 1950Jun 9, 1953Universal Oil Prod CoRegeneration of a platinumcontaining catalyst
US2699518 *Mar 19, 1952Jan 11, 1955Cohn EugeneGrid for electron tubes
US2708252 *Nov 18, 1950May 10, 1955Baker & Co IncFuel igniters
US2708253 *Nov 18, 1950May 10, 1955Baker & Co IncFuel igniters
US2737541 *Feb 17, 1951Mar 6, 1956Roger S CoolidgeStorage battery electrodes and method of making the same
US2752665 *Apr 21, 1950Jul 3, 1956Baker & Co IncGrain stabilized metals and alloys
US2786925 *Dec 31, 1952Mar 26, 1957Sprague Electric CoMetal film resistor
US2844868 *Jun 1, 1954Jul 29, 1958Sylvania Electric ProdMethod of joining refractory metals
US2856491 *Sep 27, 1952Oct 14, 1958North Electric CoElectrical contact alloy of platinum group metal and zinc and method of making same
US2861114 *May 22, 1956Nov 18, 1958Hideo NishimuraThermocouple and elements thereof
US2866692 *Jun 24, 1955Dec 30, 1958Roehm & Haas GmbhCatalytic apparatus and method for protecting a metallic catalyst against injury
US2957037 *Jul 16, 1959Oct 18, 1960Battelle Development CorpThermocouple
US2978314 *Mar 5, 1956Apr 4, 1961Fairchild Camera Instr CoCompositions for electrical resistance films
US3007990 *Mar 29, 1960Nov 7, 1961Gen ElectricThermocouple
US3009779 *Feb 24, 1954Nov 21, 1961Basf AgProduction of hydroxylamine
US3044867 *Jun 4, 1957Jul 17, 1962Messrs Aktiebolaget Svenska MeMethod for the production of metallicceramic materials
US3049577 *Aug 28, 1959Aug 14, 1962Engelhard Ind IncComposite material and thermocouple made therefrom
US3061756 *Jul 5, 1960Oct 30, 1962Monsanto ChemicalsSpark plug
US3070436 *Mar 17, 1959Dec 25, 1962Curtiss Wright CorpMethod of manufacture of homogeneous compositions
US3082277 *Apr 19, 1960Mar 19, 1963Westinghouse Electric CorpThermoelectric elements
US3099575 *Oct 20, 1959Jul 30, 1963Engelhard Ind IncThermocouple
US3109716 *Jul 22, 1957Nov 5, 1963Owens Corning Fiberglass CorpLamellar metal structure
US3159460 *Jun 28, 1962Dec 1, 1964Engelhard Ind IncComposite material
US3166417 *Apr 29, 1963Jan 19, 1965Int Nickel CoPlatinum-group metal sheet
US3229139 *Oct 18, 1962Jan 11, 1966Watson John EHigh temperature spark plug
US3305816 *Jan 27, 1965Feb 21, 1967Hitachi LtdTernary alloy strain gauge
US3305817 *Mar 25, 1965Feb 21, 1967Hitachi LtdElectric strain gauge having platinumpalladium-molybdenum alloy filament
US3306857 *Mar 28, 1962Feb 28, 1967Du PontSolid solution of w-v sc and thermoelectric element consisting of same
US3326645 *Sep 22, 1965Jun 20, 1967Beckman Instruments IncCermet resistance element and material
US3362799 *May 10, 1965Jan 9, 1968Int Nickel CoDuctile ruthenium alloy and process for producing the same
US3423248 *Sep 14, 1964Jan 21, 1969Bbc Brown Boveri & CieGas diffusion electrode for electrochemical fuel cells and method of making same
US3506494 *Dec 22, 1966Apr 14, 1970Engelhard Ind IncProcess for producing electrical energy utilizing platinum-containing catalysts
US3622310 *Jan 17, 1969Nov 23, 1971DegussaProcess of preparing noble metal materials having improved high temperature strength properties
US3665756 *Aug 1, 1968May 30, 1972Microdot IncStrain gauge temperature compensation system
US4049513 *Mar 8, 1976Sep 20, 1977Erco Industries LimitedTreatment of cell anodes
US4186110 *Jul 3, 1978Jan 29, 1980United Technologies CorporationChemical reduction of metal oxide and alloying with noble metal
US4301032 *May 21, 1980Nov 17, 1981The United States Of America As Represented By The Secretary Of The InteriorThorium oxide-containing catalyst and method of preparing same
US4980601 *Apr 24, 1989Dec 25, 1990Ngk Spark Plug Co., Ltd.Igniter plug particularly for use in very low temperature liquid fuel
US5275670 *Jul 6, 1993Jan 4, 1994The United States Of America As Represented By The Administrator Of The National Aeronautics And Space AdministrationHigh temperature, oxidation resistant noble metal-Al alloy thermocouple
US6663728Sep 4, 2001Dec 16, 2003W.C. Heraeus Gmbh & Co. KgBase metal is either 0.01-0.5 wt. % Sc or a mixture/ alloy of Sc and Zr, Y, or Ce with a total base metal content of 0.05-0.5 wt. %.
US8436520Jul 28, 2011May 7, 2013Federal-Mogul Ignition CompanyElectrode material for use with a spark plug
US8471451Jan 3, 2012Jun 25, 2013Federal-Mogul Ignition CompanyRuthenium-based electrode material for a spark plug
US8575830Jan 23, 2012Nov 5, 2013Federal-Mogul Ignition CompanyElectrode material for a spark plug
US8760044Feb 22, 2012Jun 24, 2014Federal-Mogul Ignition CompanyElectrode material for a spark plug
US8766519Jun 26, 2012Jul 1, 2014Federal-Mogul Ignition CompanyElectrode material for a spark plug
USRE34778 *Jun 9, 1993Nov 8, 1994Nippondenso Co., Ltd.Spark plug and method of manufacturing the same
USRE35429 *Jun 9, 1993Jan 21, 1997Nippendenso Co., Ltd.Spark plug and the method of manufacturing the same
DE959857C *Jun 16, 1954Mar 14, 1957Thyssen Huette AgSchutzrohr fuer Thermoelemente der Platingruppe
EP0350152A2 *May 4, 1989Jan 10, 1990Ngk Spark Plug Co., LtdAn igniter plug particularly for use with very low temperature liquid fuel
EP0982409A2 *Nov 4, 1998Mar 1, 2000C. HAFNER GmbH & Co.Process for preparing articles from rhodium powder and articles prepared thereby
U.S. Classification75/235, 502/313, 75/247, 136/236.1, 502/339, 313/141, 313/331, 136/238, 419/19, 313/311
International ClassificationB26D3/18, C22C32/00, C22C1/04, H01T13/39, H01L35/20
Cooperative ClassificationH01L35/20, C22C32/0021, B26D3/18, H01T13/39, C22C1/04, C22C1/0466
European ClassificationC22C1/04, C22C32/00C2, H01L35/20, B26D3/18, C22C1/04H, H01T13/39