Tungsten

“ It turned a dark blue and Blount 140sighed again, for he had looked up the test in advance. “If it turns blue,” a prospector had told him, “like the color of me overalls, then, sure as hell, it’s tungsten.”
“Well, well,” commented Blount, gazing mildly about, for great men do not stop to repine, “and what do you use these big scales for?”
“That’s for the quantitative test,” explained Wiley importantly. “By weighing the sample first and extracting the tungsten we get the percentage, when it’s been filtered and dried and weighed again, of the tungstic acid in the ore. ”

“ In fact, the reason why steel becomes a permanent magnet is not at all understood. Theories have been evolved, but all are open to serious questioning. The principal effect of tungsten, as conceded by leading authorities, is that it distinctly retards separation of the iron-carbon solution, removing the lowest recalescent point down to atmospheric temperature. ”

“ The air-hardening property of Mushet’s steel was contributed by a happenstance combination of tungsten and this same metal, manganese. It later developed that tungsten and chromium were the best hardening elements and these have maintained their place, though refinements of the past few years have made use of vanadium, and, more recently, cobalt in addition. Usual amounts may be said to be tungsten 14 to 25 per cent, chromium 2 to 7 per cent, with vanadium 1⁄2 to 11⁄2 per cent, and cobalt up to 4 per cent, perhaps. The carbon content is usually .6 to .8 per cent. ”

“ Many specimens of the tungsten exist without the tellurium, but every piece which has afforded tellurium has also afforded tungsten, and in greater abundance. Even in well defined crystals, both metals have been found in the same crystal, and where the external appearance was homogeneous. In other specimens a difference seems to be apparent, and a proper ore of tellurium appears to be blended with a proper ore of tungsten. This latter ore is the wolfram, composed of oxid of tungsten, or as some choose to say, tungstic oxid combined with iron and manganese. ”

“ Tungsten disulphide, WS2, is obtained as soft black acicular crystals by the action of sulphur, sulphuretted hydrogen or carbon bisulphlde on tungsten. The trisulphide, WS3, is obtained by dissolving the trioxide in ammonium sulphide or by passing sulphuretted hydrogen into a solution of a tungstate and precipitating by an acid in both cases. When dry it is a black mass which yields a liver-coloured powder. ”

“ Its value resides in the fact that it contains tungsten, an element which has wonderful powers in hardening steel.
It consists of tungsten and oxygen, but is not an oxide since there is also iron in the partnership. This [Pg 154] fact is very useful, however, since it enables the particles of wolfram to be picked out from the mass of other stuff among which they are found by a magnet. ”

“ Tungsten is also found in the mineral scheelite, a tungstate of lime. From this latter compound it may be procured by digesting finely-powdered scheelite in hydrochloric acid. Chloride of calcium is formed, together with insoluble tungstic acid. Upon heating the acid to bright redness in a stream of hydrogen gas, the metal is left behind. When thus procured it is of a dark-grey colour, but under the burnisher it may be made to assume a metallic lustre. Metallic tungsten may also be obtained by the reduction of tungstic acid, by means of charcoal at a white heat. ”

“ Tungsten Steels Steels with about 1⁄2 per cent of each of carbon and tungsten are occasionally used for manufacture of springs, and with greater amounts, e.g., 3⁄4 per cent of carbon and 5 or 7 per cent of tungsten, for permanent magnets for which they are claimed to be the best material known. ”

“ Tungsten. —The greatest tungsten-producing region is that of eastern Asia; the region of the United States and Mexico second; that of Bolivia and neighboring countries in South America third; and fourth comes the province of Portugal, Spain, and Italy. There seem to be no very large and concentrated tungsten deposits; and nearly all of those worked give signs of being easily exhausted. There may be therefore a world tungsten shortage in the future. Possibly Bolivia will prove to be the most durable field. ”

“ Of the impurities of the ore the wolframite (tungstate of iron and manganese) is the most troublesome, because on account of its high specific gravity it cannot be washed away as gangue. To remove it, Oxland fuses the ore with a certain proportion of carbonate of soda, which suffices to convert the tungsten into soluble alkaline tungstate, without producing noteworthy quantities of soluble stannate from the oxide of tin; the tungstate is easily removed by treatment with water. ”

“ She was equally astonished to find that if she read the successive octaves downward, the elements fell into families. Thus oxygen was related to sulphur, chromium, selenium, molybdenum, tellurium, and tungsten. How in the world could anything so light as oxygen be like anything so heavy as tungsten?
Sulphur was the only one of that family she knew when she met it. So she melted some crystals of sulphur and froze them into long needles, while Agricola lay by the little stove concealing his sulphur beneath his color. She knew now what a solid is, and that only crystals are true solids. ”

“ Alloys of tungsten and aluminium are used in automobile construction, and alloys of tungsten, aluminium, and copper in the manufacture of propeller blades. Tungsten steel is used in armour plates, and to stiffen the springs of cars; in the manufacture of piano-wire, and to increase the permanency of magnets. Even the rarer metals of the platinum group are finding many important applications. ”

“ Well, ordinary polished silver is a mighty poor radiator. Homely example: Try waiting for your coffee to cool if it's in a polished silver pot. Then try it in a tungsten-beryllium pot. No matter how you polish that tungsten-beryllium, the stuff WILL radiate heat. That's why an IP ship is always so blamed cold. You know the passenger ships use [79] polished aluminum outer walls. The big help is, that the tungsten-beryllium will throw off the energy pretty fast, and in a big ship, with a whale of a lot of matter to heat, the Strangers will simply give up the idea. ”

“ Tool steel containing tungsten holds its temper at high temperatures. Tools with a tungsten content of 16 per cent, to 20 per cent, can be used with the lathe running at such a speed that the chips are blued from the heat yet the temper of the tool is not affected. That is, in consequence of the high speed, about five times as much work can be accomplished as when high carbon steels are used, one man's labor being thus multiplied by five. ”

“ The nickel is added to part of the copper and the phosphide of tungsten, then the zinc, and then the rest of the copper. The alloy requires to be remelted several times, and a good deal of tungsten is lost by oxidation.
The alloy is of a fine white colour, and is very little affected by air — in fact, it is to some extent untarnishable. The specific resistance will be seen to be about one and a half times greater than that of German silver, and the temperature coefficient is about 0.021 per cent per degree C. (i.e. about nineteen times less than copper, and half that of German silver) . ”

“ No—just luck—and the fact that they're light, strong as steel almost, and can be manufactured in forms much more quickly. Only the outer hull is tungsten-beryllium. The advantage in this will be that nearly all the energy will be absorbed outside, and we'll radiate pretty fast, particularly as that tungsten-beryllium has a high radiation-factor in the long heat range. ”

“ The binoxide, WO2, is obtained when the trioxide is reduced by hydrogen at a dull red heat. This oxide is very prone to pass into trioxide or tungstate. An interesting and beautiful class of compounds of WO3, WO2, and bases are known as tungsten bronzes. The first of these was discovered by Wöhler. Normal tungstate of soda, Na2OWO3, is fused, and trioxide added to it as long as it dissolves. The product is then heated in hydrogen as long as water goes away, and the substance thus reduced is exhausted successively with water, hydrochloric acid, caustic potash ley, and again with water. ”

“ The grade of the producing deposits is on an average low. The domestic production of tungsten ore will doubtless decrease, owing to the importation of cheaper foreign ores, unless a high tariff wall is erected. Importation from the Orient and the west coast of South America should continue in reduced amounts, depending upon the ability of domestic manufacturers to obtain and hold foreign markets for ferrotungsten and high speed tool steel. In the commercial control of tungsten ores the United States has at present a strong position, second only to that of England. ”

“ In a degree this is also true of Chinese and Japanese ores.
The metallurgy of tungsten, like that of other metals, is being improved constantly, and should our ores remain in the ground for a time they will be of greater absolute value when mined, for there will be less waste in conversion. If our ores are mined now under an artificially high price, we will always pay a high price for tungsten ores, for when ours are used the ores in other countries will have diminished in quantity and increased in cost; prices would be higher and we would have to buy at the advanced rate. ”

“ Claims for better furnace practice which greatly cuts down the consumption of current and makes a saving of 90 to 96 per cent. instead of the usual 80 per cent. are also made. Several firms are making ferrotungsten powder and tungsten powder in iron tubes or other iron containers instead of in the graphite crucibles used before the war.
In the milling of tungsten ores, the tendency in this country is to get [144] away from the uneconomic method of making concentrates very high in tungsten trioxide (carrying more than 60 per cent. WO3) . ”

“ By heating a mixture of bitungstate of potash with sulphur, and washing the product with hot water, a black crystalline substance, having the above composition, may be obtained, resembling plumbago in appearance.
Of the salts of tungsten, tungstate of baryta has been used as a substitute for white lead in painting; but the most important of these is the tungstate of soda, described below. See also Tungstic glue.
TUNGSTATE OF SODIUM. Na2WO4. This salt is used for rendering linen, cotton, and other fabrics uninflammable; also as a substitute for stannate of sodium as a mordant in dyeing. ”

“ In incandescent lamps, the tungsten filament, through which the electric current passes, grows more luminous than the carbon filament of the early days of the art. There were faults of 'offsetting' and 'sagging,' however, affecting the efficiency of the first tungsten filaments. 'Offsetting' occurs when, during heating in the use of the lamp, the filament forms crystals which extend their boundaries across the entire diameter of the filament, substantially perpendicular to its axis. The crystals in the filament thus come to have an appearance, somewhat analogous to the joints in a bamboo rod. ”

“ Judging from the rocks in which they frequently occur, tin, molybdena, tungsten, and wolfram are ranked as the most ancient metals; uranium and bismuth stand next, "having been found in veins in transition or secondary strata." Gold and silver are considered comparatively new; copper, lead, and zinc occur in deposits of various ages; arsenical pyrites ranks as an old product, cobalt as new, magnesia is of intermediate, and iron ores are of all ages. ”

“ Tungsten Bronze Pigments are expensive and rarely employed. They are obtained by fusing sodium or potassium tungstate in a porcelain crucible and gradually adding tungstic acid until the mass has an acid reaction. Tin dioxide is then added in quantity sufficient to neutralise the tungstic acid; the mass is cooled and finely powdered. According as potassium or sodium tungstate is used, a violet or reddish pigment is obtained which exhibits the peculiar metallic lustre of a bronze powder. ”

“ American capital controls the tungsten deposits within its own borders and in Mexico, and is largely interested in Bolivia and China. Before the war Germany controlled probably half the tungsten output, the other half being divided among the United States, England and France. At the present time, the control through ownership of mines and smelters is as follows: Great Britain 54 per cent.; United States 35 per cent.; Japan 4 per cent.; France 4 per cent.; and Germany 1 per cent. ”

“ Pure tungsten is bright steel gray, very hard, and very heavy. It is one of the most brittle of all the metals and for that reason was put to very few uses before the invention of the tungsten lamp. It was most commonly used, however, in various steel processes, to harden the metal.
365 From the time Edison invented the incandescent lamp in 1879, right up to the present electricians have tried to get a better electric light filament. ”

“ A change in the manner of using tungsten steel, by which a thin plate of high-speed steel is cemented to a more ordinary steel bar so as to form the cutting edge of a lathe tool, has made the demand for tungsten less than it would have been had the old practice been followed of making the whole tool of high-speed steel. ”

“ During this time, mines everywhere must remain idle until a demand again arises, except for those mines required to furnish tungsten for Germany, Austria and Russia and the small quantity required by Sweden, Norway and Italy. If industries in Germany, Austria and Russia recover so that they can buy and use tungsten, Germany will have regained in the ores that will be eagerly offered by producing nations needing a market, a part of the trade she has lost. ”