September, 1923
INDUSTRIAL A,VD ENGINEERING CHEMISTRY
normally contain small amounts of oxides, sulfides, and gases--particularly hydrogen, carbon monoxide, sulfur dioxide-as well as in many cases, arsenides, nitrides, carbides, etc., in addition to their metallic impurities. The former are either present in the original metals or, oftener, absorbed from the refractories or slags in the melting furnace or from the fuel gases or furnace atmosphere. All these impurities may exercise a profound effect on the course of manufacture of the metals and on their properties in the finished form, and many are known to do so, but unfortunately that knowledge is very meager. It can generally be expressed in some such manner as this: “The bronze was brittle because it was oxidized,” or “Aluminium is very sensitive to the absorption of gases during melting.” Many individuals are beginning to realize the necessity of obtaining precise knowledge along these lines of it and are trying to attack the problem as best they can. More has been said and done on the gas absorption problem than on any of the other features of this subject, since the production of sound and dense castings and ingots is almost a s i n e qua non of the manufacturing nonferrous industry. The whole subject is, however, a difficult one and will require the development of a new investigative technic, but it is nevertheless extremely important. Exact knowledge of the chemical relations between the metals and the impurities to which they are subjected during manufacturing and refbing must be the basis for economical operation of mill and foundry; rejections of off-heats and defective castings will be eliminated when these matters are better understood. Furthermore, such knowledge must be the basis for the broad development of the secondary metal industry which was forecast above. Pure metals may be dealt with in some ignorance, but impure ones require knowledge and care both in their preparation and in their use. Complete knowledge of slag and gas reactions with metals at high temperatures will permit of their refinement and separation from undesirable impurities.
FABRICATION OF METALS ~
897 N ALLOYS D
Few, perhaps, realize the study and effort necessary to produce a new product and to fit it for industrial utilization. It is not enough to discover and market a new alloy of useful properties; if it is to enjoy any general use, methods must be developed by which it may be fabricated into the various forms desired. This often requires more time and effort than the discovery of the product itself-and, conversely, a new product is valuable somewhat in proportion as the methods of its fabrication are generally known and understood. The details of various developments along these linesmachining, welding, forging, drawing, spinning, casting, etc.would be of little interest here. Two developments of this sort, however, seem to be increasing in favor and usefulness. One is the development of the centrifugal casting of metals, particularly of tube and ring forms, which seems to offer much promise both in economy of cost and increase of quality. The other is not very new-the increased use of chill molds in the production of castings which have to be duplicated a large number of times, and in particular the increased use of pressure die castings. Chill castings are now being produced in brass and bronze and pressure die castings of intricate form in lead, tin, zinc, and aluminium base alloys. Only the lack of a satisfactory mold material prevents the possibility of producing pressure die castings in brass and bronze which could thus be cast to size and require little or no machining.
CONCLUSIOSS
Out of the mass of research work now in progress in the nonferrous industries have been selected those features which appear to be the most fundamental and to have the greatest permanent significance for the industry. Extremely valuable and interesting work along more special lines, such as fundamental studies of the structure of metals and alloys by microscope and X-ray, the production of corrosion-resistant coatings by new and old methods, the study and diagnoNEW ISDUSTRIAL USESFOR SOKFERROUS sis of the many curious so-called “diseases” to which some METALSAND , ~ L L O Y B alloys are subject, the development of the use of the electric The business depressions following the war have stimulated furnace in both the rolling mill and the brass foundry, the development work in each group to an unusual degree look- cooperative research initiated by the Engineering Division ing toward the increased commercial application of its prod- of the National Research Council, and the American ucts, arid many coiicerns have actually organized products- Foundrymen’s Association on the use and reclamation of development departments with engineering and scientific foundry sands, have necessarily been neglected. personnel. The copper producers have gone still farther What has been said will a t least illustrate the direction and have initiated cooperative development work through of research in the nonferrous industries, as far as its objects the instrumentality of the Copper and Brass Research Associa- and purposes are concerned. As to its method, which is of tion. vastly greater ultimate importance, enough has been said Most of this work is intimately connected with, and indeed to demonstrate: that within these industries, as elsewhere, based upon, research work, of which the results are contin- not only is increasing effort being put on the solution of ually yielding information as to new products with valuable the daily engineering problems, but the volume of fundaproperties and new applications of newly discovered valuable mental research is growing also; research activity is growing, properties of old materials. Much of this material is in not only in volume, but in depth and self-consciousness. direct response to the more and more diversified and severe requirements of the metal users, each requiring a material for a special purpose and to meet new and exacting conNew M o t o r Fuel ditions. I t is going on in all the nonferrous groups, but The Australian commonwealth government is manifesting perhaps it is most active in the aluminium, magnesium, great interest in experiments with eucalyptus oil as a motor nickel, and zinc groups; the producers of some of the rare fuel. C. M. Dyer is said to have demonstrated that it can metals have also been active-for example, metallic tantalum be used in petrol engines, with efficient means of vaporization. The only difficulty he has encountered is that it will has recently been the subject of development. not start an engine from cold without priming, but its calorific This development and research activity represents acommon value is high. Tests made with cheap cars showed 24 miles purpose but hardly a trend, unless we realize with sajisfaction to the gallon with gasoline; 28 miles with half gasoline and half the general value to all industries of the mass of practical eucalyptus oil; and 36 miles on eucalyptus oil alone. Eucalyptus oil mixes with gasoline, benzene, and alcohol, and acts as a deand useful information which is daily being secured in the carbonizing agent. The main difficulty of manufacture on an effort. extensive scale would be in securing laborers to gather the leaves.
