SCIENCE AND INDUSTRY. 
ae NEW JAPANESE STEEL PLANT. 
Designs have been prepared in the United States of America for a 
steel plant, intended for shipment to the Kinshu works at Yawata, 
_Japan, the estimated cost of which is £750,000. The whole plant will 
be electrically driven. The initial plant will include three 50-ton basic 
open-hearth furnaces, a 20-unit producer plant, an 84-in. plate mill, and 
a 24-in. structural mill. Later, a motor-driven, 35-in. blooming mill 
will be installed. The three basic open-hearth furnaces are served by 
21 Smythe gas producers. The 84-in. three-high plate mill, which is 
nearly ready for shipment, is of the Lanth type, and will be driven by a 
2,000 h.p. motor, through herring-bone reducing gears and pinions; 
the motor, running at 420 R.P.M., makes the mill speed 56 R.P.M. Since 
the company has its own blast furnaces, coal and iron ore mines, and 
fire-brick plant in China, it will be the most completely self-contained 
organization in the Far Kast. 
TUNGSTEN POWDER AND FERRO-TUNGSTEN. 
Tungsten powder and ferro-tungsten are required in the manufacture 
of high-speed steel. Ordinary tool steel, which contains no tungsten, 
loses its temper and its hardness, and so becomes incapable of cutting if 
it be heated to a temperature well below incipient red heat. As a result, 
the cutting speed of ordinary tool steels is limited to that below which 
the heat produced is sufficient to draw the temper or produce this soften- 
ing. By adding tungsten to the steel in quantities up to as high as 
20 per cent. (but generally not exceeding some 15 or 16 per cent., and 
even less), the steel is changed in quality in such a way that it does not 
lose its hardness at a dull red heat. Cutting operations can then be 
carried on at an increased speed, and the output of all machine tools 
built sufficiently strong to withstand the increased stresses, can be 
increased to about two and a-half times that possible when ordinary 
carbon steel is used. This property of tungsten is, of course, enormously 
valuable in all cases where output is of paramount importance, and in 
carrying out the shell programme its use was almost essential. Tungsten 
steels are also required in the manufacture of magnets for magneto- 
electric ignition machines and other purposes. ‘The tungsten is added 
to the steel in the form of tungsten powder and ferro-tungsten. Before 
the war, although attempts had been made to carry on the industry in 
England, they always failed by reason of German competition, and, in 
fact, before the war, Germany supplied practically the whole world with 
tungsten powder and ferro-tungsten—this notwithstanding the fact that 
the richest mines were in British territory. During the war the manu- 
facture was successfully established in this country, and its importance 
was deemed so great that it was started in many other countries also, 
notably America, France, Italy, and Japan. In addition to the form of 
tungsten powder just considered, there is another particularly pure form 
of tungsten powder which is required in quite small quantities for com- 
pressing into slugs and hammering out into solid tungsten objects such 
as electrodes for wireless valves, X-ray tubes, &e. These slugs are also 
drawn down into tungsten wire used in the manufacture of metallic 
filament lamps. The British output of this particular form of very 
pure tungsten is not at present up to requirements, though it is hoped 
that very shortly we shall be able to meet our own needs and also carry 
on an export trade. 3 
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