Corrosion-Resisting Alloy lndust ry F. L. LA QUE, International Nickel Company, New York, N.Y. ONSIDERATION of the relation of the alloy industry to the chemical phase of the preparedness program naturally focuses attention on the well established fact, so recently confirmed, that present practice in defense against war has increased the importance of materiel among the resources of the nation. It is unnecessary here to dwell upon the sweeping changes that have occurred in the chemical industry since 1918, or to recall that while these changes were not aimed a t war preparedness, they have contributed considerably to the ability of the nation to defend itself. It will suffice merely to list some of the most important chemicals, most of which are being produced now by methods or from raw material sources greatly different from those in common use a t the time of World War I ( 2 ):
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Acetic acid Acetone Ammonis Benzene Sodium hydroxide Chlorine Ethyl alcohol Hydrochloric acid
Methanol Nitric acid Phenol Picric acid Potash Soda ash Sulfuric acid Toluene
The modern production of all these chemicals has been made commercially feasible by, and is to a considerable extent dependent on the availability of metals and alloys able to withstand the destructive effects of corrosive attack, temperature, and pressure, and capable of protecting the finished products from harmful contamination. A comparison of lists of alloys available in 1918 with those in commercial production in 1940 shows a tremendous increase in the variety of compositions in use (3). Inde@, the outstanding difference between the two periods is the commercial availability today of many alloy compo ions which were either unknown or in the early stages of evelopmgt during the former period. I n this group may be men stainless steel, heat-resisting alloys, Monel,#conel, Hastelloys, and Illium. The metal producers now better understanding of the requirements of the che dustry and in addition the ability to modify a l l q c o m to take care of most requirements. It seems safe, t to predict that if developments in the war preparedness program of the chemical industry should indicate t w n e e d of new materials for construction of processing equipment, t e corrosion-resisting alloy industry will be in a position to m&t the demand quickly. I n reviewing some of the most important advances in the corrosion-resisting alloy industry since 1918, attention should be directed first to the family of alloys known as the stainless steels. The commercial development of these alloys dates from about 1914 when the Firth Company of Sheffield, England, produced about 50 tons of stainless steel containing approximately 13 per cent of chromium for cutlery. Production of a similar alloy for the same purpose was undertaken in this country in 1915 by the Firth Sterling Steel Company. The introduction of the lower carbon content straight chromium and the austenitic chromium-nickel alloys designed primarily for resistance to corrosion and oxidation dates from about the same time. Consequently, the years since the firfit World
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War cover practically the whole period of commercial growth of the stainless steels. The extent of this growth is indicated by comparing the 50 tons of cutlery stainless made by Firth in 1914 with the 178,000 net tons of stainless steel ingots and castings of all types produced in this country in 1939 (1). The increasing diversity in types and application of stainless steels is illustrated by noting that in 1939 the composition of alloy which includes the original cutlery grades of stainless steel represented only about 9 per cent of the total production, whereas the group of austenitic alloys which are of greatest interest to the chemical industry accounted for a t least 43 per cent of the total ingot production. It may also be noted that the chemical industry was estimated to have used in 1939 only from 6 to 7 per cent of the stainless steel produced. It seems evident, therefore, that even without adding anything to ingot production facilities the stainless steel industry is well prepared to take care of any immediate demand from the chemical industry for larger quantities of stainless steels for equipment construction. I n most instances stainless steels are produced in plants manufacturing other types of steel. Some of this melting and rolling equipment, in use for other purposes, is available to meet increased requirements of stainless steel production. The nonferrous metals and alloys have also kept pace with the changing demands of the chemical industry. I n the case of the high-nickel alloys, a large mill devoted solely to their production was put into operation at Huntington, W. Va., in 1922. This mill has made the country independent of the former European sources of rolled nickel and has ample capacity to take care of any additional expansion in the demand for rolled nickel, Monel, and Inconel. , Developments in nonferrous alloys have been chiefly in the dire+n of adding higher strength to their inherent resistance to chemical attack. Examdes include tellurium lead with its better creewroperties, the$ilicon bronzes and beryllium cophich are strong and hard, and K-Monel and 2-nickel combine high corrosion resistance with strength propermparablj+to those of alloy steels. xamples of nonferrous alloys which have been ded for particular purposes since 1918 may be mentioned p p e r - n y alloys containing from 20 to 30 per cent which re of particular value for tubes in heat exchangers and marine condensers where corrosion and erosion conditions exceptionally severe, and the alloy Inconel which i especially useful in resisting corrosive effects at elevated t k p e r a t u r e s , as in the case of exhaust manifolds on highpower airplane engines. Other examples are the Hastelloy group of nickel-molybdenum alloys which are exceptionally resistant to chlorine compounds and hydrochloric acid, and Illium (nickel, chromium, molybdenum) which is resistant to both nitric and sulfuric acids, as well as to a great variety of other chemicals, and which recently has been made available in rolled forms in addition to castings. The economical fabrication of heavy corrosion-resisting processing equipment has been made possible by the introduction on a commercial scale of steel plates clad with corrosionresisting metals and alloys, including platinum and silver, which are attached to the base metal by various processes. I n addition, practical methods have been devised for installing corrosion-resistant linings in existing vessels.
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SEI"IY3MBEI1, 1940
INDUSTRIAL AND ENGINEERING CHEMISTRY
While many rnetallurgists have been active in the improvement of older materials of construction and the introduction of new ones, others in the industry, in cooperation with chemists and chemical engineers, have been engaged in increasing the knowledge of the corrosion-resisting properties of both old and new materials and in defining their fields of usefulness. A review of published data on corrosion will show a tremendous increase in the information available in 1940 as compared with 1918. This better understanding of the proper use of corrosion-resisting metals and alloys should be of value in ensuring the most efficient use of availahlo materials in connection with the expansion of the chemical industry that will form part of the general preparedness program.
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it may he stated, therefore, with considerable assurance that the corrosion-resisting alloy industry is in an excellent position not only to take care of a considerable increase in demand for their present products, but also to produce new a.lloys to meet new demands and to guide the chemical industry in tlicir proper selection, fabrication, and use.
Literature Cited (1) Lipport. T . W., Iron Age. 145, 33-40 (Mag. 23. 1940). (2) Kohinson.C. S.. Chern. & Met. Eng., 46, i64 (1939).
(3) Woiciman, N. E.. and Uernbhtt, A. J., "Engineering Alioys", Am. SOC.for Metais, 1936.
PLANT EQUIPMENT I). H. KILLEFFER 60 East 422nd Street. New York, N.
Y.
as possible for the same reason, design requiring necessarily to be fitted to the material used. Within the past two decades of swift development of chemical industries, the variety of construction materials available to the equipment builder has increased substantially. 1. Standard equipment of various kinds can be produced Whereas two decades ago the materials available for resisting more easily and quickly than special designs. chemical attack were strictly limited in number, today the 2. Special metals and alloys are important but not vital in list is very broad. Among the materials likely to be difficult the preparedness picture. to provide, chromium is outstanding. Otl~erwiseit seems nn3. In general, the chemical process industries have relikely that any important shortage of a material considered cently modernized and are in excellent condition for of strategic importance will occur. Trouble may he exassuming the burden of added output. perienced in getting par4. Where special skills ticular alloys of various arc involved, as in types on account of deceramic and special mand for other purposes. machine work, esThese troubles must be tablishment of prihandled by priorityestabority systems ,and lished by government orrelief from present der. IIowever, with the legislative r e s t r i cvariety of alloys and other tions on hours of corrosion-resistant matework may he essenrials available SOT building tial to meeting fast chemical PTOCW equipproduction schedment, even low-priority ules. jobs should he handled without serious difficulty. It should hardly he At worst, this might renecessary to amplify a quire return to some of the statement 80 obvious as corrosion-resistant met.& onr first Doint. Yet observations by numerous and matt.rials which have builders OS equipment exbeen discarded in favor of modern alloys, but even tending over tong periods that is not fatal to the of time suggest that in picture. peace and war the ongiFurthermore, the quanneers' arbitrary departure tities of alloys required in from standard or nearstandard design is their equipment for PTOCISS industries is small as comgreatest trouble. Changes from s t a i i d a r d designs pared with other demands. which seem to be minor Recent modernization DTOgrams have placed indusmay actually involve seritries of this kind in exous losses of time when cellent p o s i t i o n . This speed is essential. SimiPhotograph Ivan Wide World Pholoa, Ino. Iarlv. would tend to minimize ~.materialsusedshould be standardized as nearly requirements for normal WELDINQSTAINLX~SS STEELTO FORM AN INTEORAL MASS
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EVERAL important points are emphasized by a recent surrey of nearly three hundred firms manufacturing equipment for chemical processing.
