摘要:
Thermoplastic compositions useful for producing metallic moldings containA) 40-70% by volume of a sinterable pulverulent metal or of a pulverulent metal alloy or of a mixture thereof,B) 30-60% by volume of a mixture ofB1) 50-100% by weight of a polyoxymethylene homopolymer or copolymer andB2) 0-50% by weight of a polymer which is immiscible with B1) and can be thermally removed without leaving a residue, or a mixture of such polymers,as binder, andC) 0-5% by volume of a dispersant.
摘要:
Alkali metal nitrates are prepared by supplying the anode space of an electrolysis cell, separated from the cathode space by a perm-selective cation exchange membrane, with alkali metal chloride solution and at the same time supplying the cathode space with a nitric acid/alkali metal nitrate solution whose alkali metal nitrate concentration is not less than 10% by weight and whose HNO.sub.3 concentration is of from 0.1 to 10% by weight, and withdrawing from the cathode space a solution whose pH does not exceed 5.
摘要:
Stabilized acicular ferromagnetic chromium dioxide is prepared by reductive treatment of the chromium dioxide with Na.sub.2 [Fe(CO).sub.4 ], and this material is present in magnetic recording media.
摘要:
The invention relates to a method for producing metal bodies by mixing metal compound particles with a binding agent and compacting them to form shaped parts, whereby the binding agent is subsequently removed and the metal compound is reduced to metal by gassing the same with a reductive gas at high temperatures. The reduction is carried out at temperatures lower than the sintering temperature of the reduced metal compound so that the formed reduced shaped bodies, while maintaining their original dimensions to a large extent, have a density less than that of the metal compound used. The metallic matrix obtained in such a manner can be subjected to a post compaction by applying mechanical forces. High-strength steel parts having very low residual porosities and a high geometric tolerance are obtained by sintering the matrix at usual sintering temperatures after compaction.
摘要:
The application relates to a process for removing nobler metal ions than iron, especially copper ions, from acidic process and waste waters by reduction under an inert gas atmosphere with carbonyl iron powders which have previously been subjected to a thermal treatment with hydrogen to remove nitrides and carbides. This process results in residual metal ion content
摘要:
Chlorate is removed from aqueous caustic soda by reducing with iron pentacarbonyl and separating off the resulting iron oxide containing precipitate.