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A glossary of mining and metallurgical terms

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A GLOSSARY OF MINING AND METALLURGICAL TER>[S. 83<br />

will not sensibly harden by being quenched in water while at a red<br />

heat, shall be called ingot-iron (Germ., Flusseisen ; Fr., fer fondu).<br />

i. That all such compounds, when they will from any cause so har-<br />

den, shall be called ingot-steel (Germ., J^lussstahl ; Fr., acier fondu).<br />

This projiosed classification does not cover ordinary c^st or pig iron.<br />

It is a classification <strong>of</strong> the jnalleable compounds only. The Institute<br />

has recommended its use in papers <strong>and</strong> discussions, except as to the<br />

term loeld, for which a substitute was desired, <strong>and</strong> meanwhile the<br />

continuance <strong>of</strong> the old term wrought, though in a somewhat wider<br />

significance, was suggested. The resolution <strong>of</strong> the Institute concludes<br />

as follows : " It being understood that the ingot-iron <strong>and</strong> ingot-steel <strong>of</strong><br />

this classification constitute, taken together, what is now commer-<br />

cially known as cast-steel, including the so-called low or s<strong>of</strong>t cast-<br />

steels." Bessemer-steel is made by decarburizing cast iron in a con-<br />

verter. (See Bessemer process.) Blister or cement-steel h made by car-<br />

burizing wrought iron bars by packing them in charcoal powder <strong>and</strong><br />

heating without access <strong>of</strong> air. It is melted in crucibles to cast-steel, or<br />

hammered {tilted) to shear-steel (for cutlery, etc.), or rolled to spring-<br />

steel. Paddled steel is made by arresting the puddling process before<br />

wrought iron has been produced, <strong>and</strong> thus retaining enough carbon<br />

in the bath to constitute steel. Natural steel is a similar product,<br />

obtained from the refining <strong>of</strong> cast-iron. Crucible cast-steel is steel<br />

made by the fusion in crucibles, either <strong>of</strong> blister-steel, or puddled<br />

steel, or steel-scrap, or other ingredients <strong>and</strong> fluxes which will produce<br />

the desired quality. Cast-steel in its widest sense, as now employed,<br />

comprises all malleable compounds <strong>of</strong> iron produced by fusion, in-<br />

cluding therefore the Bessemer <strong>and</strong> open-hearth metal. Open-hearth,<br />

called also Martin-Siemens steel, is made in the reverberatory furnace<br />

(almost invariably a gas-furnace on the Siemens regenerative system,<br />

since an intense temperature is required) by the reaction, in the<br />

fused bath, <strong>of</strong> cast-iron with wrought-iron, iron-oxide, or iron ore.<br />

At a certain stage <strong>of</strong> the process a deoxidizing or recarburizing agent<br />

{spiegeleisen, ferromanganese)j is added. Chrome-steel is a crucible<br />

cast-steel in which chromium is a constituent. Tungsten or Wolf-<br />

ram-steel is a steel containing tungsten. Phosphorus-steel is a steel<br />

in which the amount <strong>of</strong> phosphorus exceeds that <strong>of</strong> carbon. Damas-<br />

cus-steel is a laminated mixture <strong>of</strong> steel <strong>and</strong> wrought iron. India-<br />

steel or Wootz is manufactured in India direct from the ore.<br />

hole.<br />

Stemmer, Xewc. See Tamping-bar.<br />

Stemming, Xewc. The tamping put above the charge in a bore

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