Malleable iron

“ The difference between the “best quality of wrought iron” and the lower classes of steel is so slight that, to separate them, would be like naming the hour that sweet cider becomes 67 sour. Iron is used in three states; as crude or cast iron, as steel, and as wrought iron, the difference only depending on the relative amount of carbon with which the metal is combined—cast iron containing a larger proportion of carbon than steel, and steel more than wrought or malleable iron.
I have nothing whatever against Mr. Baldridge, this being my first dealing with him ”

“ Iron is seldom found pure and malleable in the earth; yet it is much seldomer found in the mineral state, properly so called, than any of the other metals: for most iron ores are scarce any thing more than a ferruginous earth mixed in different proportions with unmetallic earths and stones. Some of them, however, contain also volatile minerals, such as sulphur and arsenic; and therefore it is necessary to roast the iron ores, like all others, before you attempt to extract the metal out of them. ”

“ Wrought iron will occasion scintillations, somewhat of the same appearance, and steel, also, in greater abundance; and hence both are employed in sundry compositions. But the particular character, beauty, and brilliancy of Chinese fire must be attributed, first to the iron, and secondly to its peculiar state of combination with carbon and oxygen; for, we have said, that malleable iron, (which is deprived in a great measure of these substances in the operation required for its preparation) , produces an effect far inferior to cast iron. ”

“ To those who are best acquainted with the nature of fluid iron, it may be a matter of surprise that a blast of cold air forced into melted crude iron is capable of raising its temperature to such a degree as to retain it in a perfect state of fluidity after it has lost all its carbon and is in the condition of malleable iron, which, in the highest heat of our forges, only becomes softened into a pasty mass. ”

“ We say that the iron made by the ancients was in reality a variety of what we now term wrought iron, for it fulfilled three of the principal requirements for wrought iron, viz., it was not necessarily melted during production, it was a malleable metal, and it contained cinder or slag, but practically no carbon. ”

“ It is only slightly malleable, except when specially treated, is rigid and has great resistance to crushing, but is more or less brittle and not adapted to tensile strains. Wrought iron is nearly pure iron, and in modern metallurgical processes is usually obtained by removing the carbon and other impurities from cast iron. ”

“ B. The native nickeliferous or meteoric iron is very malleable, often cellular, but sometimes compact, and in parallel plates, which pass into rhomboids or octahedrons. It is naturally magnetic, and by its nickel is distinguishable from terrestrial native iron. Macquart, in describing the famous mass found at mount Kemir in Siberia, says that the iron is perfectly flexible, and fit for making small instruments at a moderate heat; but in too strong a fire, the metal becomes short, brittle, and falls into grains under the hammer. ”

“ To persons conversant with the manufacture of iron, it will be at once apparent that the ingots of the malleable metal which I have described will have no hard or steely parts, such as are found in puddled iron, requiring a great amount of rolling to blend them with the general mass, nor will such ingots require an excess of rolling to expel cinder from the interior of the mass, since none can exist in the ingot, which is pure and perfectly homogeneous throughout, and hence requires only as much rolling as is necessary for the development of fibre ”

“ Iron is a metal of a bluish colour, of the greatest hardness, the most variable in its properties, and the most useful of all the metals; so that without it it is hardly possible for any people to make great advances in arts and civilization.
This metal readily parts with its phlogiston, so as to be very subject to calcine, or rust, by exposure to the air. The same is evident by the colours which appear on its surface when exposed to heat, and also when it is struck with flint; the particles that fly from it being iron partially calcined. ”

“ Pure iron like pure gold is homogeneous, but unlike gold it is rarely pure. If gold be kept in a melted condition a sufficiently long time, all extraneous matters may be burnt away, but if iron be kept in a hot state too long it will be burnt away itself. Pure iron appears to be ductile, but pure iron will not melt. To form cast-iron, a quantity of carbon must be mixed with the pure iron. If the quantity of carbon be less in amount, steel is the result. ”

“ It is so, and that is one of its worst properties. Every liquor, and even a moist air corrode it. But the rust of iron is not pernicious: on the contrary, it is a very useful medicine.
Geo. I have heard of steel drops and steel filings given for medicine.
Tut. Yes; iron is given in a variety of forms, and the property of them all is to strengthen the constitution. Many springs are made medicinal by the iron that they dissolve in the bowels of the earth. These are called chalybeate waters, and they may be known by their inky taste, and the rust-coloured sediment they leave in their course. ”

“ Pure iron is a chemical curiosity which looks very much like silver. As obtained from its ores, or as it occurs in Nature, iron always has some impurities with it, such as carbon, silicon, sulphur and phosphorus, and these are highest in the crudest iron such as “pig-iron.” Its malleability and ductility are only a little less than for gold and silver, and so it has a wide range of qualities for use by man. It is only rarely found native in minute grains in some of the dark lavas. ”

“ During the melting of the charge the heat is kept as high as possible and the molten iron is “puddled,” i. e., stirred, by the “puddler” or his helper with a “rabbler” or iron bar. In order to take out the phosphorus and sulphur, which for best results should be removed before the carbon is eliminated, the heat of the furnace is lowered somewhat as soon as all of the pig has melted, and some iron oxide is mixed into the “bath” of molten iron and cinder. Most of the phosphorus and sulphur are chemically acted upon and pass into the cinder which covers the iron. ”

“ Some kinds are broken up to be used as foundation for roads; others are granulated by being run into water, and so made into cement. Over in Germany, where the ores are rich in phosphorus, they grind up the linings of the furnace to make phosphatic fertilizers for the farmers.”
“Then,” said Dr. Crandon, “the making of iron involves the use of chemistry, doesn’t it?”
“It certainly does,” answered Mr. Prescott; “from the chemical composition of ores to the finished product. We are learning a great deal just now from the chemists about steel alloys. ”

“ First it must be mentioned that iron frequently contains injurious contaminations, sulphur, phosphorus, etc., and that it must have been very difficult for these primitive metallurgists to remove these contaminations, and to introduce the proper quantity of carbon into the iron. We must also consider that even a good, pure steel would be a useless product unless it was worked by a skillful and experienced smith. Finally, iron is much more rapidly destroyed by oxidation than bronze. ”

“ Water saturated with fixed air dissolves iron, and makes a pleasant chalybeat.
The calx of iron gives a green colour to glass.
[Pg 107] Iron readily combines with sulphur. When they are found combined by nature, the substance is called pyrites.
The union of phosphoric acid with iron makes it brittle when cold, commonly called cold short; and the union of arsenic makes it brittle when hot, thence called red short.
Iron unites with gold, silver, and platina, and plunged in a white heat into mercury, it becomes coated with it ”

“ With such a volume of weakening constituents and particularly with the graphite flakes cutting through and separating the iron grains as the photomicrographs show, can one wonder that cast iron is fragile—more so than steel or wrought iron? ”

“ But just as the chemist will tell you that there are no substances which are absolutely insoluble, just so does cast iron appear to be extremely brittle only when compared with the iron alloys of considerably less brittleness. ”

“ That is, as soon as a vessel costing millions of dollars leaves the docks, she enters into active competition for a place on the junk pile."
The greatest improvement that can be imagined in the iron situation will be in the discovery and use of alloys or mixtures of iron with other materials. Steel, the strongest of all forms of iron, is an alloy of iron and carbon, and for various purposes these are further mixed with nickel and silicas. Many other alloys have been discovered within the last few years, and each makes possible new uses for iron requiring greater strength. ”

“ Almost all the comforts and conveniences of civilized life are obtained by iron. You may imagine, then, the condition of the Papal States, when I state that iron is all but unknown in them. It is about as rare and as dear as the gold of Uphaz. And why is it so? There is abundance of iron in our country; water-carriage is anything but expensive; and the iron manufacturers of Britain would be delighted to find so good a market as Italy for their produce. Why, then, is iron not imported into that country? ”

“ Prescott, “just remember three things: fuel, blast, and hammer—power, of course, behind the hammer. It’s the different variations that men have been making on those three things that have brought iron where it is to-day.
“Iron ore has so many things besides iron in it that the problem has always been how to get the impurities out.
“The old blacksmiths used to put it in the fire and hammer it; put it back in the fire and hammer again, until they worked most of the other things out. They made what is called forge iron. ”

“ Yes, iron is hard and makes a pillar of strength in time of need. But he who forges out of it weapons and tools that are at once delicate [362] and resistless, knows that it will humbly shoe the feet of horses, and cut the household bread, and will make for others besides Lombardy a kingly crown. And when iron is truly on fire, nothing commoner or softer nor anything more yielding—not even gold itself—can glow with a more steadfast and fervent heat to warm the hands and hearts of men. ”

“ Pig-iron, or, as it is sometimes called, crude iron, being saturated with carbon and oxygen, and containing also a portion of scoria, is too brittle for any other purpose than castings. Many of these, such as stoves, grates, mill-irons, plough-irons, and kitchen utensils, are commonly manufactured at blast furnaces, and in many cases nearly all the iron is used for these purposes. In such cases, the metal is taken in a liquid state, from the hearth, in ladles. ”

“ It is so highly 75refined that it can hardly be called steel at all but is often called “open-hearth iron” or “ingot iron.” It is probably the purest iron on the market in commercial quantities to-day. While in the chemical laboratory iron of considerably greater purity can be made, for a commercial product this is remarkably pure, seldom containing more than 1⁄4 per cent of elements other than the metal, iron. ”

“ CHAPTER XI. IRON—NICKEL—COBALT—ZINC—CADMIUM. IRON.
Iron rusts or oxidises very readily, and, consequently, is rarely found in the metallic state in nature; such native iron as is found being generally of meteoric origin or imbedded in basalt and other igneous rocks. It chiefly occurs as oxide, as in magnetite, hæmatite, and in the brown iron ores and ochres. Chalybite, which is carbonate of iron, is an ore of great importance. Iron is found combined with sulphur in pyrrhotine and pyrites, and together with arsenic in mispickel. ”

“ The reduction of the ores of iron into metallic iron is in principle very simple, because when the oxides of iron are strongly heated with charcoal, hydrogen, carbonic oxide, and other reducing agents, [5] they easily give metallic iron. But the matter is rendered more [322] difficult by the fact that the iron does not melt at the heat developed by the combustion of the charcoal, and therefore it does not separate from those mechanically mixed impurities which are found in the iron ore. ”

“ When iron contains more than 2.2 per cent. of carbon it is hard, brittle, and more easily melted, and is known as crude iron, or raw iron, because it is derived from the raw product,—black ore. The melted crude iron is called cast iron. Iron is ductile when it contains less than 2.2 per cent. ”

“ Iron is one of the most timid of metals. It has a great disinclination to be alone. It is also one of the most altruistic of the elements. It likes almost every other element better than itself. It has an especial affection for oxygen, and, since this is in both air and water, and these are everywhere, iron is not long without a mate. The result of this union goes by various names in the mineralogical and chemical worlds, but in common language, which is quite good enough for our purpose, it is called iron rust. ”

“ Open-hearth iron is practically pure iron, having no constituents or slag inclusions which materially affect its properties.
2. Wrought iron, for all practical purposes, is pure iron 86except for its content of slag. It is the only one of the iron family which does normally contain slag.
3. Neither open-hearth iron nor wrought iron contains carbon in appreciable quantities.
4. The distinguishing and active element of the steel family is carbon. With increase of carbon the hardness of the alloy increases as does its tensile strength, but the ductility (elongation or stretch) decreases. ”