Alloys containing potassium

A few of the relations of the alkali metals with one another have been investigated. Potassium with about 30 per cent, of sodium forms an alloy which is liquid at ordinary temp., and which has the appearance of mercury. This becomes pasty at 8°, and solidifies at a lower temp. If the alloy contains 77 per " /o" S>"x cent, of potassium, it remains liquid even... 

Platinum alloys containing from 0 5 to 20 per cent, of tantalum are hard, withstand heat, as well as the action of adds and fused potassium hydrogen sulphate, and are more resistant to the action of aqua-regia than platinum.8 They possess the mechanical properties off platinum-iridium alloys and are less expensive the relative quantities, of tantalum and iridium required to produce the same hardness and mechanical resistance are stated to be 1 5. Platinum-tantalum alloys, hence have been recommended for various purposes in place of platinum or platinum-iridium. Tantalum can also be coated with platinum, andl can then be utilised in high-temperature work. ... 

Interesting support to the belief that the compound Pd2Pb can exist is afforded by the results of experiments 5 to determine the difference of potential between various alloys and pure lead in a normal solution of lead nitrate. The alloys were prepared by melting the palladium and lead under a mixture of lithium chloride and either potassium or barium chloride. Alloys containing less than 33 per cent, of palladium have a potential practically identical with that of pure lead, whilst those containing more than this amount of palladium exhibit a higher potential, which at first rapidly increases with the palladium. Between 20 and 90 per cent, of palladium the alloys are harder than the individual components, a maximum occurring with 65 per cent, of palladium. 

Kvokova and Lainer electrodeposited pure Re and Re-Cr alloy on Mo substrate. For the deposition of Re itself, two baths were used one containing perhhenic acid, and the other containing potassium perrhenate. In the first bath, the discharge of hydrogen ions was enhanced. The authors attributed the low overpotential of hydrogen on Re to its lattice parameter (a = 2.758 A). However, a justification to this theory has not been proposed. For both deposition of Re and Re-Cr alloy, the concentration polarization was foimd to be insignificant compared to the activation polarization. 

GENETRON 113 (Allied Signal) (76-13-1) Reacts violently with chemically active metals, barium, calcium, lithium, potassium, sodium, and powdered aluminum, beryllium, magnesium, potassium-sodium alloy, titanium, zinc. Contact with alloys containing more than 2% magnesium or with hot surfaces can cause decomposition with the release of... 

Materials which readily form alloys with Pt (nonmetals P, As, Te, Si, B and C) or metals which melt at low temperatures (Pb or Sn) or substances which liberate these materials during ignition or melting processes can not only damage but even destroy platinum apparatus. This also holds for all melts containing potassium hydroxide, sodium nitrate, or mixtures of the alkali hydroxides or alkali carbonates with sodium nitrate melts containing peroxides, cyanides or sulfides are particularly Injurious to crucibles. 

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