Mongolia has extensive mineral deposits; copper, coal, molybdenum, tin, tungsten and gold account for a large part of industrial production.
In the meantime, ternary light alloys appear the most satisfactory, and tungsten and copper, or tungsten and nickel, seem to be the best substances to add.
Steels containing as much as 12% of tungsten are now used as a material for tools intended for turning and planing iron and steel.
A number of persons conceived the idea of making a filament of tungsten on account of its peculiar characteristics, which seemed to be just about the ones needed for the ideal electric light globe.
This inventor was John Allen Heany, and his patents were rejected finally, the rights of the tungsten filament going to the General Electric Company.
While the tungsten lamp is far from perfect, it is a great advance over other forms, and an advance in the right direction, for it gives a better light with a smaller consumption of electricity than other types.
Meanwhile, several investigators began work with tungsten and a similar metal called tantalum because of their extremely high melting points, high resistance, and other technical characteristics favourable for an incandescent filament.
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.
Tungsten is a metal that for a great many years some of our most prominent chemists and scientific investigators declared could not be put to the use we see it here," answered the man.
For years they had no success because the metal was so very brittle that they could do nothing with it, but finally a filament of pressed tungsten was brought out.
This delicacy of the tungsten lamp is the reason the fixtures for most of them are placed in stationary positions, rather than on swinging drop cords, as is the case with so many carbon incandescent lights.
The next step, and the one which a great many scientists had declared impossible, was the manufacture of a tungsten wire through a regular process of drawing it out through dies to the desired length, and in the desired thickness.
Thady Shea knew more about prospecting for tungsten than he did about cooking.
Here is the new Tungsten electric lamp, which uses half the current, at low voltage, but doubles the light; the very dazzling symbol of efficiency.
This resulted in the production of refractory metallic filament lamps made of osmium, tantalum, tungsten and other rare metals.
The zirconium and tungsten wire lamps are equal to or surpass the tantalum lamp in efficiency and are capable of giving light, with a useful commercial life, at an efficiency of about one watt per candle.
Tungsten lamps are made by the processes of Just and Hanaman (German patent No.
Patents have also been taken out for lamps made with filaments of such infusible metals as tungsten and molybdenum, and Siemens and Halske, Sanders and others, have protected methods for employing zirconium and other rare metals.
In some cases, however, other substances replace carbon as the radiating body; in the incandescent gas light certain earthy oxides are utilized, and in metallic filament electric lamps such metals as tungsten or tantalum.
Just out, side the door of Midshipmen Farley and Page there lay on the floor tiny glass fragments of what had been an efficient sixty-candle-power tungsten electric bulb.
Now one of these tungsten bulbs, when struck smartly, explodes with a report like that of a pistol.
These tungsten lights don't explode like that, except when rapped in some way.
Say, did you hear a tungsten bulb blow up in the night!
So firmly convinced had Adams been that Dan was about to make a denial that now, with the incident broken in two by the report of the tungsten bulb, Lieutenant Adams really believed that had so denied.
It was not until long after that Darrin found out the explanation of the accident to the tungsten bulb.
The explosion of the tungsten bulb was too great a puzzle for either officer to solve.
I'll tell him of the blowing up of this tungsten light.
Soon after Dave and Dan were called up, Farley, listening with his door ajar half an inch, slipped out and hit the tungsten burner a smart rap just in the nick of time to save Dan Dalzell's Navy uniform to that young man.
A tool of the old sort could not cut at a rate faster than thirty feet a minute without overheating, but the new tungsten tools will plow through steel ten times as fast and can cut away a ton of the material in an hour.
The German method of making the lamp filaments is to squirt a mixture of tungsten powder and thorium oxide through a perforated diamond of the desired diameter.
The tungsten wires in the electric lamps are about .
A recent rival of tungsten both as a filament for lamps and hardener for steel is molybdenum.
But the student of today studies his lesson in the light of a tungsten wire and relieves his mind by listening to a phonograph record played with a "tungs-tone" stylus.
If tungsten ores were more abundant and the metal more easily manipulated, it would displace steel for many purposes.
To get the tungsten into wire form was a problem that long baffled the inventors of the world, for it was too refractory to be melted in mass and too brittle to be drawn.
That which bears the poetic name of star-stone, stellite, is composed of chromium, cobalt and tungsten in varying proportions.
Further investigation showed that steel to which tungsten and manganese or chromium had been added was tougher and retained its temper at high temperature better than ordinary carbon steel.
But although Burma had belonged to the British for a hundred years they had not developed its mineral resources and the tungsten trade was monopolized by the Germans.
Before the war nearly half of the world's supply of tungsten ore (wolframite) came from Burma.
All the ore was shipped to Germany and the British Admiralty was content to buy from the Germans what tungsten was needed for armor plate and heavy guns.
In the United States before the war tungsten ore was selling at $6.
In 1911 Glenn Curtiss produced his epochal flying-boat, Just and Hanaman invented the tungsten electric light, and Drager his pulmotor, for reviving persons who have been asphyxiated or partially drowned, by forcing oxygen into their lungs.
This has now been ousted by the much more efficient tungsten filament lamp.
The manufacture of drawn-wire filaments thus became possible, and the tungstenfilament lamps which are now produced will stand a considerable amount of rough handling.
Ordinary arc lamps, and even flame arc lamps, are being displaced by the modern high-candle-power gas-filled tungsten lamp.
The earlier tungsten lamps were very fragile, owing to the brittleness of the filament.
Later, a process was discovered whereby tungsten could be made malleable.
Mushet's special steel," that is, his tungsten alloy tool metal, was taken over by the Sheffield firm of Samuel Osborn and Company.
These patents include, besides variations on his "triple compound" theme, his important patent on the use of tungsten for cutting tools, later to be known as Mushet steel.
Each strand was a fine wire of two-phase material--the harder phase being borazon, the softer being tungsten carbide.
If (as is generally the case) tungsten is present the solution will be blue.
The tungsten minerals have a high specific gravity (6 to 7.
The tungsten may be conveniently reported in this form, although it is probably present as a lower oxide.
For the assay of minerals containing tungsten these reactions are only occasionally taken advantage of for testing or purifying the separated tungstic acid.
Tungsten itself is insoluble in nitric acid or aqua regia; but is converted into tungstic acid (WO{3}) by prolonged and strong ignition in air.
Molybdenum high-speed steel is more expensive thantungsten high-speed steel, but is said to wear better.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "tungsten" in a variety of sentences. We hope that you will now be able to make sentences using this word. Other words: gold; iron; lead; metal; silver
