Abstract: Processes are described for preparing pure ammonium molybdate from impure roasted molybdenum concentrates. An aqueous solution of nitric acid, ammmonium sulfate, and ammonium nitrate is contacted with impure molybdenum concentrate to solubilize a major portion of the impurities. The resulting molybdenum concentrate is digested in ammonium hydroxide under conditions that maximize iron precipitation and removal. The resulting ammonium molybdate solution is separated from the sludge and further purified by chelating cation exchange resin in the ammonium form.

Abstract: A low insertion force connector which includes an outer housing and an inner housing having a pair of sidewalls and an upright section intermediate the sidewalls with a respective row of contacts positioned intermediate the upright section and a respective sidewall wherein the sidewalls and the upright section each have contact engaging portions to cause the opening and closing of the contacts depending on the position of the inner housing relative to the outer housing.

Abstract: A zero or low insertion force connector having a cam for moving an inner housing relative to an outer housing wherein the respective housings each include cam engaging surfaces which provide positive engagement with the cam during both the opening and closing of the contacts.

Abstract: A rotatable cutting insert of the type having a shank depending from a head portion and having a hard insert mounted therein, includes an improved insert comprising a heat conducting base section disposed within a cavity in an intermediate section.

Abstract: A process is disclosed for producing high purity tantalum oxide from impure tantalum oxide. The starting tantalum oxide is dissolved in a hydrofluoric acid solution and insolubles are removed. The hydrofluoric acid solution containing the tantalum values is adjusted to a pH of from about 6.0 to about 8.0 with a base to precipitate tantalum which is separated from the mother liquor. The tantalum precipitate is then dissolved in an oxalic acid solution, the pH adjusted to from about 5.1 to about 5.5, and the resulting solution digested to precipitate a high purity tantalum compound which is separated. The high purity tantalum compound is then digested in hydrochloric acid to dissolve the compound and then precipitate pure optical grade tantalum oxide which is then separated from its mother liquor.

Abstract: A removable and indexable insert includes forwardly and rearwardly projecting faces forming cutting edges with side surfaces and concave end surfaces forming side cutting edges.

Abstract: Processes are described for preparing pure ammonium molybdate from impure roasted molybdenum concentrates. An aqueous solution of nitric acid and ammonium nitrate is contacted with impure molybdenum concentrate to solubilize a major portion of the impurities. The resulting molybdenum concentrate is digested in ammonium hydroxide under conditions that maximize iron precipitation and removal. The resulting ammonium molybdate solution is separated from the sludge and further purified by chelating cation exchange resin in the ammonium form.

Abstract: In a process is disclosed for recovering rhenium from tungsten and rhenium bearing material by oxidizing and fusing the starting material, solubilizing the tungsten and rhenium values, passing the resulting solution through a strongly basic anion exchange resin to retain the rhenium, removing the rhenium from the resin with an organic stripping liquid of tributylphosphate and hydrochloric acid, washing the remaining rhenium off the resin with water, combining the water and organic to form a two phase system in which the organic phase contains the major portion of the rhenium, and contacting with aqueous ammonia to strip values.

Abstract: A plasma spray powder comprising a uniform powder blend of silicon nitride and a plasma meltable metal produces a coating having some of the properties of silicon nitride.

Abstract: A fine powder is prepared by directing a high velocity stream of molten droplets into a cooling fluid to form rapidly solidified powder. The powder is subjected to comminution at an energy sufficient to fragment at least a portion of the particles which are not completely rapidly solidified. The fragmented particles are removed to give a powder containing a greater proportion of rapidly solidified particles than the original mixture.

Abstract: A rotatable cutting insert of the type having a shank depending from a head portion and having a hard insert mounted therein, includes an improved insert having a conically shaped tip section, a base section and an intermediate section with the maximum diameter of the tip section smaller than the diameter of the base section.

Abstract: Tantalum is recovered from an impure source containing niobium, tungsten, titanium, iron, and other impurities by a process comprising mixing the impure source with an alkali metal carbonate, drying the resulting mixture, heating the dried mixture to convert the tungsten to a soluble form, leaching to solubilize the tungsten, digesting the resulting leached solids containing tantalum in hydrochloric acid to solubilize iron values and a portion of the titanium values, dissolving the leached solids containing tantalum values in hydrofluoric acid, adjusting the pH of the resulting solution to form a first tantalum precipitate, dissolving the first tantalum precipitate in oxalic acid adjusting the pH to form a second tantalum precipitate, dissolving and digesting the second tantalum precipitate in hydrochloric acid solution to form a third tantalum precipitate of high purity.

Abstract: A process is disclosed for producing a high purity tantalum precipitate from an impure source by dissolving in a first hydrofluoric acid solution and digested to form a first precipitate of tantalum which dissolved in hydrochloric acid. The resulting solution is heated to form a second precipitate of tantalum which is dissolved in another hydrofluoric acid solution and digested to form a third precipitate of tantalum. The third precipitate of tantalum is then dissolved in an oxalic acid solution with the pH being adjusted to form another tantalum precipitate which is converted to tantalum oxide.

Abstract: In a process for producing fine cobalt metal powder by reduction of a cobalt hydroxide precipitate, the cobalt hydroxide precipitate is heat treated prior to reduction at a selected temperature for reducing the Fisher Sub Sieve Size of the finally produced cobalt metal powder.

Abstract: Metal carbide is reclaimed from scrap by sorting the scrap to separate pieces of cemented carbide having similar composition and grain size and treating the separated portion to form metal carbide grains which may be resintered with metal binder to obtain cemented carbides having grain characteristics similar to the starting material.

Abstract: A pressable and sinterable metal carbide grade powder consists essentially of a uniform mixture of a refractory metal carbide powder, a metal binder powder, and from about 0.5 to about 5 percent by weight of an organic amide having a melting point greater than about 120 degrees centigrade.

Abstract: A process is disclosed wherein tungsten is recovered from hazardous waste material containing said tungsten, arsenic, and other impurities which can consist of magnesium, phosphorus, and silicon and the resulting waste is treated to render it nonhazardous according to EPA standards for arsenic. Said process involves digesting said hazardous waste material in an aqueous solution of an alkali metal hydroxide, adjusting the pH of the resulting solution to about 11.0 to about 13.0 with NaOH to precipitate essentially all of the magnesium and silicon species, filtering the digestion mix to remove the solids from said resulting solution which contains about 80 to about 100% of said tungsten and essentially none of said magnesium and said silicon, slurrying the hazardous solids in hot water, and adding to the slurry a ferric salt solution to precipitate ferric hydroxide, filtering this mixture to give a solid which passes the EPA standard test for solids with respect to arsenic.

Abstract: In a process for producing fine size cobalt metal powder from scrap material containing brazing compositions, the silver ions are removed by cementation with iron to form an insoluble mixture which is subsequently treated with concentrated hydrochloric acid to solubilize the silver which is then precipitated as silver chloride.

Abstract: A powder metallurgical alloy which comprises a solid solution of molybdenum and from about 10 to about 98 percent by weight tungsten has a dispersed phase of hafnium carbide. The alloy is prepared by mixing powders of hafnium carbide, carbon, molybdenum and tungsten, and subsequently pressing, sintering, and age- or work-hardening.

Abstract: In a process for producing pure ammonium paratungstate from ammonium tungstate solutions containing tin, sulfide is added to the ammonium tungstate solution in an amount sufficient to form a soluble complex of the sulfide with the tin. The solution is then evaporated to a volume at which essentially all of the tungsten is in the form of insoluble ammonium paratungstate and essentially all of the tin is in the mother liquor in the form of a soluble complex along with other impurities. The solid ammonium paratungstate is then separated from the mother liquor by filtration.