Metallurgy Of Cast Iron

214 METALLURGY Ot UAbT IKUW,
ganese; that for this reason manganese can often high and still soft castings be obtained. The bette cupola is fluxed and the higher its temperature, t more the manganese will be decreased. In mak < or remelting iron, manganese is affected in a n i; ner somewhat similar to silicon. * A hot working f ' nace will send the manganese into the pig, wher*. cold working furnace will send it into the slag, ; i -requires high heat to make manganese combine \v the iron, when making it.
A phenomenon peculiar to manganese is to be < t in the opposite results which manganese exerts \\ ' in the pig, in process of being melted, and when * added as ferro-manganese to soften hard grades molten metal, as is practiced by some founders. T atithor cannot explain the phenomenon better than 1 here inserting comments by Mr. Alexander E. OUT < bridge, Jr., in a paper presented by him before i '* Franklin Institute, February 2, 1888:
A remarkable effect is produced upon the character of hare! ." * by adding to the molten metal, a moment before pouring it ?M a mould, a very small quantity of powdered ferro-manganese, • one pound of ferro-manganese in 600 pounds of iron, and I" * oughly diffusing it through the mass by stirring with an rod. The result of several hundred carefully conducted ex; ments which I have made enables me to say that the tra\ * strength of the metal is increased from thirty to forty per <•• the shrinkage is decreased from twenty to thirty per cent., the depth of the chill is decreased about twenty-five per r» while nearly one-half of the combined carbon is changed free carbon; the percentage of manganese in the iron is not sibly increased by this dose, the small proportion of manga j: which was added being found in the form of oxide in the so-The philosophical explanation of this extraordinary effect i my opinion, to be found in the fact that the f erro-manganesu .»R. C. Hindiey, M. Hoskins, Harvard College, Havemeyer University, Henry Hiels Chemical Co., Isabella Furnace, Iron Gate Furnace, Iroquois Iron Co., Illinois Steel Co., Jefferson Iron Co., Kittan-ning Iron & Steel Co., C. A. Kelly Plow Co., Lebanon Furnace, Longdale Iron Co., Lackawanna Iron & Steel Co., Logan Iron........................ 16,720 " t-