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By C. S. Barrett, O. R. Trautz

PREVIOUS investigations have shown that lithium is body-centered cubic from near its melting point to the temperature of liquid air1,2,3 Nevertheless there was an incentive to search again for a transformation at low temperatures: C. Zener4,5 has remarked that the low value of the elastic modulus (11 - C12)/2 of body-centered cubic metals and alloys implies a rapid increase in free energy with decreasing temperature, which would favor the occurrence of a transformation; also the shear movement to which this modulus applies is one that can transform a body-centered cubic structure into a slightly distorted face-centered cubic structure. It was confirmed that lithium does not transform spontaneously at liquid nitrogen temperature, but it was found that a transformation can be induced at this temperature by cold working the metal,6 and at slightly lower temperatures a different transformation occurs spontaneously. Transformations were also found in solid solutions of magnesium in lithium. THE NATURE OF THE TRANSFORMATIONS Before presenting a detailed treatment of the technique used and the specific data obtained, it would be well to give a brief survey of the general characteristics of the transformations. A new crystal structure begins to form spontaneously in a specimen when it is cooled below a critical temperature. In lithium the structure appears to be close-packed hexagonal; in the Li-Mg alloys most of the diffraction lines (but not all) are near those for hexagonal lithium. The transformation proceeds as the temperature is lowered and soon stops if the temperature is held constant or raised. The course of the transformation on cooling is indicated by the curve at the lower left of Fig I. This curve is drawn in stepped fashion because the transformation goes by discrete steps with audible clicks. Because of the similarity to the decomposition of austenite into martensite in steels, it seems appropriate to designate the beginning of the spontaneous transformation on cooling as the Ms point. On heating to room temperature after the low temperature treatment only the usual BCC structure is found. On heating, the low temperature modification begins to disappear at a temperature which will be designated as Ac. The transformation on heating is halted when the rise in temperature is halted. The temperature must be raised 40 to 50°C above Ac before the reversion is complete-an interval which is sensitive to the rate of heating and to the time of holding at temperatures above Ac. This behavior on heating thus has similarities also to the formation of martensite in the cooling of steels.

Jan 1, 1948

By Stephen P. Holt

During the spring and summer of 1946, the Bureau of Mines put down 8 churn-drill holes and 9 diamond-drill holes, totaling 3,535 feet of bore, at the Blewett zinc-lead deposit in Jo Daviess County, Ill. Attention of the Bureau of Mines was first directed to this deposit by the Illinois State Geological Survey, which had investigated the Blewett mine. In the opinion of the Survey and the Bureau of Mines, the record of production and results of drilling previously done on the property were considered sufficient justification for continuing investigation to the north and south along a projection of the trend. This report describes the work done by the Bureau on this, property and presents the data obtained.

Jan 1, 1948

By W. H. Kerns

The Simon & Coles manganese deposit in Sherman Valley, Bedford County, Pa., was investigated by the Bureau of Mines during the fall of 1942. Two churn-drill holes; 65 and 75 feet deep were bored, and 8 channel samples were taken. Manganese occurs at this property in the form of psilomelane and manganiferous iron as replacement of the red sandy shale of the Much Chunk-formation. Two cars of manganese ore had been shipped by the owners in 1940, of which one averaged 10.9 percent manganese and the other 21.3 percent manganese. One car of hand-sorted manganese ore that averaged-45 percent manganese was shipped in 1942.

Jan 1, 1948

By Bernard Lewis

The ignition problem: for a layer of firedamp bordering on a cloud of detonation products is evidently considerably more complicated than in the usual laboratory ignition experiments, in which a well-defined volume of gas is heated and the occurrence of ignition is observed after an induction period. An atmosphere of firedamp exposed to the detonation of a high explosive is subjected to heating by shock-wave compression and thermal conduction and to intermixing at the interface of the firedamp atmosphere and the cloud of deto¬nation products. Although a reliable physical-chemical analysis of the problem is not yet possible, one may nevertheless form a general view of the role of compression waves and the processes of heat transfer and diffusion at the interface. Near the mouth of a shot hole, or near a freely suspended cartridge, the firedamp atmosphere attains very high temperatures by adiabatic compression, and it is certain that such temperatures are sufficient to initiate chemical reaction. The pressure wave pattern is reproducible from one test charge to another if the initial experimental conditions are held constant; on the other hand, experiments on firedamp ignition do not yield a reproducible threshold condition for ignition, but only an ignition probability. Thus, the induction periods are sufficiently long that there is time for the compressed', heated gas layers to undergo random changes that may quench or promote ignition. Therefore, the analysis of the ignition problem hinges primarily on the discovery of the random events that modify the chemical reaction in the activated gas layers.

Jan 1, 1948

By Graham W. Marks

In broadening the utility of spectrochemical methods 9f analysis of ore samples 3,4/ a procedure employ in the total energy method, has been adapted to determination of silver in ores. Silver is the first element in group I of the periodic table to be studied in the Bureau of Mines program. Two silver lines in the spectrum, Ag X\ 3280.683 and 3382.89lR were used in the study, and the problems that had to be overcome were: (1) Influence of extraneous elements on line intensities, (2) preparation of standard curves, and (3) improvement in equipment and technique to increase accuracy. Sodium, potassium, sulfur, selenium, iron, cobalt, and nickel yielded low intensities and hence low results, particularly on the samples high in silver, but addition of 60 percent or more of lime counteracted these effects. One calibration curve must be used for samples low in silver and other for those high in silver. The chocks with fire assaying were close enough for preliminary or exploratory investigations, and the method is much more rapid.

Jan 1, 1948

By J. F. Haseman, J. E. Davenport

In the brown rock phosphate fields of Tennessee there are large deposits of phosphate matrix in which quartz is a major constituent of the gangue, and which cannot be beneficiated by the conventional washing process to yield a concentrate of suitable grade for use in the electric furnace. A huge tonnage of high-grade phosphate concentrate is produced in the Florida pebble district from low-grade siliceous feed. However, the characteristics of the low-grade siliceous Tennessee ore are such that flotation under the conditions employed in treating the Florida ore1,2 results in inadequate beneficiation. Investigation of Flotation Methods Flotation has been used in 'Tennessee primarily to produce a concentrate of premium grade by moderate enrichment of a marketable grade of phosphate. 3,4 A secondary use was to increase the recovery of phosphate from the fines (down to approximately 200 mesh) from medium-grade ores with a concomitant moderate increase in over all grade.3,5 It was considered desirable to investigate methods of improving the grade of washed products from low-grade siliceous Tennessee ore when these products were substantially below the requirements for use in the electric furnace. The present paper describes the results of a laboratory-scale study of factors that affect the beneficiation of such siliceous phosphate ore by flotation. The primary objective of the investigation was to ascertain the conditions under which the ore could be made to yield a concentrate suitable for reduction in the electric furnace. It was assumed that a phosphate concentrate for electrothermal reduction should contain at least 26 pct P2O5 and should have a weight ratio of silica to lime of not more than 0.80. Since a concentrate of moderate grade can be used in the electric furnace, and since, as Grissom4 has shown in detail, the ore will not bear the cost of expensive treatment, the study of collectors was limited to the relatively inexpensive fatty acids. A secondary objective was to determine whether a portion of the phosphate could be recovered in a grade suitable for treatment with phosphoric acid to produce 45 pct superphosphate. The ore consisted of variably cemented sand interlayered with clay. The sand layers were composed of grains of quartz, phosphate, and clay embedded in a matrix of clay and phosphate. Some clay was finely disseminated in the phosphate grains. Little massive high-grade phosphate was present. The material used in the flotation tests was a washed sand that had been separated from the ore in a bowl classifier at the TVA phosphate-washing plant. The percentage composition of the sand was as follows: P2O5, 20; SiO2, 40; CaO, 29; Fe2O3, 2; Al2O3, 3; F, 2.3. The particle-

Jan 1, 1948

THE. extraordinary volume of work done in this period, and the multiplicity of subject matter, make a year-by-year historical account undesirable, if the account is not to be an assembly of unrelated fragments. We shall, instead, undertake to narrate the development in this period of each of the branches of the subject separately, hoping that their interrelations will be self-evident. There is a certain arbitrariness in the selection of subject matter in the following sections. The development of important engineering alloys-for example, high-speed steel-is disregarded, for it is the primary purpose of this account to relate the advances in ideas, the growth of the science of metals; other historical accounts relate these parallel advances. Nor are advances in techniques stressed, though occasionally the most important are noted; nor is the progress described in allied fields such as welding, cutting, etc.; for though these developments have very frequently made possible the advances herein related, they are far too numerous to recount in anything short of a ponderous volume. There is a more serious arbitrariness, however; it is not an easy matter to draw the boundaries of physical metallurgy, and some contiguous subjects have been omitted that perhaps should have been included, such as, for example, corrosion, gases in metals, the magnetic behavior of metals and alloys, and certain other fields in the physics of metals. REACTIONS IN ALLOYS--DIFFUSION Many of the reactions occurring in alloys proceed by the operation of the process of diffusion in the solid state: the annealing of mixed powders to form alloys, the homogenization of castings or forgings, the freezing of alloys, the treatment of clad metals, the loss

Jan 1, 1948

By Bruce I. Thomas

The occurrence of tin-bearing gravels along Tozimoran Creek in central Alaska has been known for a number of years. In September 1944 the Bureau of Mines investigated an area approximately 1,000 feet long and 200 feet wide along Tozimoran Creek to deter-mine the cassiterite content of the stream gravels, which are about 4 feet deep and covered by 3 feet of overburden. Nine trenches and two shafts were excavated, from which samples of the underlying gravels were taken. This report contains a discussion of sampling methods and tables giving the results of analyses.

Jan 1, 1948

By Constantine C. Popoff

During 1946 several high-grade limestone deposits in western Washington were examined by the Bureau of Mines. This report presents the data obtained from investigation of the Sauk Mountain deposits in east-central Skagit County, Washington, The investigation consisted of transit and topographic surveys and sampling. The areas selected for sampling were first cleaned by blasting; channel samples up to 40 pounds Were cut where practical. Chip samples averaging 30 pounds were taken where channel samples could not be cut. A total of 21 samples in the Sauk Mountain area were taken and analyzed. The locations of the samples are shown in figures 2 and 4, and the analyses are listed in tables 1 and 2. This investigation is a part of a long-range program of general investigation of mineral resources for future industrial development of the Pacific Northwest. The Sauk Mountain deposits were investigated for the purpose of disclosing new sources of high-purity limestone, which could be mined and shipped at low cost to Seattle and other industrial cities in the Pacific Northwest.

Jan 1, 1948

By E. O. Binyon

"INTRODUCTION The Gibellini manganese—zinc-nickel deposits, are in southeastern Eureka County, Nev, T. 15 N., R. 53 E. M.D.B.M. 27.5 miles south of Eureka, the county seat.The partly explored deposits, locally known as the Black Iron or Gibellini property, were examined in May 1944 by an engineer 3/ of the Bureau of Mines, who recommended that the deposits be explored further by means of core drilling. The proposed program called for drilling six diamond—drill holes, or eight if necessary, and for trenching at two places — 200 feet northeast and 280 feet west of the shaft on the main deposit.In 1946 the project was set up, and In July, of that year diamond drilling as started. Six holes were drilled for a total length of 1,198.5 feet. No trenching or other exploratory work as done. Work on the project was stooped. October 30, 1946.OWNERSHIPAccording to county records, the property comprises a group of 13 unpatented lode claims, and ownership is divided among Louis P. Gibellini,Louis P. Gibellini and wife (both of Eureka, Nev.), and the International Smelting & Refining Co., of Salt Lake City, Utah. Five claims of the group - the Black Iron No. 1, Black Hill No. 2, Manganese No. 3, Flat No. 1, and Flat No. 2 - are owned by Gibellini. Three claims - the Black Hill No. 1, Black Iron No. 3, and Manganese No. 4 are owned jointly by Mr. and Mrs. Gibellini, and the International Smelting & Refining Co. owns the remaining five - the Black Iron No. 4 and No. 5, and Black Hill Nos. 4, 7, and. 9."

Jan 1, 1948

By R. Philip Hammond

Monazite has had a Cinderella-like history. Although nearly go per cent pure rare-earth compound (rare-earth phosphate) it was sought at first not for the rare earths but for the sake of a minor constituent—thorium. The thorium, essential for the Welsbach gaslight mantle, was present in only small quantities and the principal constituents, the rare earths, were largely discarded. Gradually, however, the rare earths have developed uses of their own and today have left the thorium far behind in value. Occurrence Monazite was first produced commercially about 1886, in North Carolina, where it was collected in small sluices by farmers who found it in stream beds on their land. The deposits were later exploited on a larger scale, but were mostly abandoned in a few years, when monazite from Brazil came upon the market in far larger quantities. Domestic production ceased entirely in 1906. The Brazilian source is still active, together with Indian, Dutch East Indies, and Australian deposits. Several other localities in the United States have yielded monazite, but none of these has produced commercially as yet. Monazite occurs originally in pegmatite~ and gneisses, through which, unfortunately, it is scattered in highly dispersed form. All commercially useful deposits consist of transported monazite sands liberated by erosion and concentrated by the action of water, which has sluiced away lighter materials and concentrated the heavy (D = 5.0 to 5.2) grains of monazite, together with ilmenite, zircon, garnet, and other dense minerals. The Carolina deposits were in stream beds; most of the other deposits mentioned are on or near the seashore, where the action of the waves has served to concentrate the monazite. In most cases today, the sands are worked to obtain the ilmenite and zircon, as well as monazite. The minerals are separated by means of sluices, dry tables, and magnetic separators, and each is finally obtained nearly pure. No crushing or grinding is necessary. The concentrates are shipped in fiber bags. Composition of Monazite As Table I illustrates, monazite is the anhydrous orthophosphate of the cerium Table i.—Typical Analysis of a Monazite Sand (India). Per Cent Thorium oxide............................. 8.1 Cerium oxide.............................. 30.6 Lanthanum oxide........................... 15. 7 Neodymium oxide.......................... 10.5 Praseodymium oxide........................ 2. 9 Samarium oxide............................ 1.0 Europium. gadolinium, and terbium oxides.... 0.7 Yttrium oxide.............................. 0.4 Dysprosium, holmium, erbium. thulium, ytterbium. and lutecium oxides................. 0. 1 Silicon oxide............t................... 2.4 Calcium, aluminum, and iron oxides.......... 1.0 Uranium oxide............................. 0.3 Phosphorus pentoxide....................... 26. 2 a The values given for the rare earths following samarium are approximate. being based upon analyses of concentrated fractions derived from monazite. The composition given represents Travancore monazite carefully freed from other minerals. goup of rare-earth elements. A small amount of yttrium and terbium group phosphate is also present.* All the rare-

Jan 1, 1948

By A. H. Lang

Introduction Tin continues to be as much a strategic metal as it was during the war. This situation is due to the fact that the tin mines in the major producing areas of Malaya and the Netherlands East Indies have not yet reached their pre-war production. Moreover, the world requirements for tin in certain fields, particularly in the food pack industries, are steadily increasing. At present, tin is still under International allocation by the Combined Tin Committee, of which Canada is a member nation. This Committee reviews periodically the availability of refined tin for export from the producing countries and makes allocations of tin to ensure equitable distribution to the consumer countries. In 1947, availability permitted an allocation of only 70 per cent of stated requirements. From 1935 to 1938 the price of tin in New York averaged 49 cents a pound and during the war the price in Canada was controlled under a subsidy programme at levels from 60 to 70 cents per pound. Just recently, this price has been raised to 96 cents. The value of the Canadian production amounts to about half a million dollars annually and the whole of this is obtained as a by-product of the lead-zinc-silver ores of the Sullivan mine in British Columbia. In 1947 Canada's imports of tin were 3,961 long tons valued at over $6,000,000. In addition, tin plate to a value of $8,000,000 was imported from the United States; the tin content of this is estimated to be from 650 to 700 long tons. An increase in domestic production would, therefore, be of great national importance, and the present high price may make the search for and development of tin deposits more attractive than it has been in the past. Although no one can foretell what future prices will be, there is reason to believe that, unless there is a drastic downward revision of production costs, the price will be maintained at present levels for some years. A number of tin occurrences are known in Canada, but none of these have been developed for their tin content alone.

Jan 1, 1948

By Clinton C. Knox

During the latter part of 1943, a magnetometric survey was conducted by the Geophysical Division of the Bureau of Mines at the Mahopac magnetite mine, Putnam County, N. Y., in an endeavor to locate a segment of the ore body that reports state was cut off by a fault. The Mahopac mine was abandoned about 1895 after producing nearly 1,000,000 tons of high-grade magnetite iron ore. The results of the investigation indicate the termination of the ore body by "pinching", or a displacement of such magnitude as to place any extension at a considerable distance from the original are body. This report describes the work done on the project and presents the data obtained.

Jan 1, 1948

By Stephen P. Holt

In the fall of 1946 and spring of 1947 the Bureau of Mines put down five inclined diamond-drill holes totaling about 3,100 feet of bore to test for the possible eastward extension of the Royal Princess ore deposit in Jo Daviess County, Ill. Attention of the .Bureau was first directed to this property by the Illinois State Geological Survey. The history of production of the Royal. Princess mine and reports as to the size and nature of the deposit were considered justification for investigating the trend of the mineralization. This report describes the work done by the Bureau of Mines and presents the data obtained.

Jan 1, 1948

By A. Goldberg, T. E. Tietz, J. E. Dorn

INTRODUCTION THE concept that the flow stress for plastic deformation of metals in the work hardening range is a function of the instantaneous values of the strain, strain rate and test temperature was promulgated by Ludwick1 many years ago. This thought has been more or less a guiding principle throughout the immediate period of development and growth of mechanical metallurgy. It has been tacitly assumed or knowingly applied to many investigations on the plastic behavior of metals. Spurred by the theoretical interest and practical importance of the plastic behavior of metals, many investigators have attempted to determine empirical, semi-empirical, and theoretical equations2-18 relating the flow stress with the strain, strain rate, and temperature. Although the applications of such equations have been extensive, the experimental verification of the existence of a mechanical equation of state is weak. Furthermore, some of the available evidence on plastic flow appears to suggest that no simple functional relation between stress, strain-rate, strain and temperature can exist. The mechanical equation of state demands that [a = a(e, E, T)[I]] Where o = true stress = load/instantaneous area e = true strain = In Instantaneous gauge lengths initial gauge length e = true strain rate T = temperature] This formulation implies that [da] is an exact differential. Therefore the flow stress (o) is a function of the instantaneous values of the strain (e) the strain rate (e) and the temperature (T), independent of the previous mechanical or thermal history. Having reached a certain strain, strain rate, and temperature, by any path whatsoever, a definite and fixed value of the flow stress should be obtained. One check on the validity of the mechanical equation of state is easily obtained. Consider the following three tests on the stress-strain curve at constant temperature: [A. Strain at rate [ei] B. Strain at rate i2 C. Strain at rate [Ei] to [ei] and continue test at i2] A graphical representation of possible results of such tests are shown in Fig I. If, for strains greater than [el], test (C) data coincide exactly with the data from test (B), as shown in Fig Ia, a limited verification of the mechanical equation of state is obtained for the range of strain rates from [ii] to [e2]. But if the data from test (C) differ from those of (B) beyond strain [el] where the strain rate is changed from [e,] to [€2i] the mechanical equation of state is not

Jan 1, 1948

By R. B. McElwaine

From November 1943 to April 1944, the Bureau of Mines put down 18 churn-drill holes aggregating 2,571 feet of bore in an investigation of the virtually abandoned zinc deposits of the north-central Arkansas district, principally in Marion, Boone, Searcy, and Newton Counties. The ore of this area occurs in flat-lying sedimentaries of the Mississippian and Ordovician ages. Much of the zinc is in the form of carbonate and silicate, although some sulfide has been produced. Preliminary studies resulted in selection for investigation of the Big Hurricane mine in northwest Searcy County, the Spies mine in northeast Newton County, and the Coon Hollow mine in eastern Boone County The comparatively large production of th.ese properties in the past was a factor in the selection. This report describes the work accomplished in the investigation and presents the data obtained.

Jan 1, 1948

By B. M. Larsen

Jan 1, 1948

By Milton Fies

Introduction The first experiment in underground gasification of coal in the United States was conducted at Gorgas, Walker county, Alabama, under a co-operative arrangement between the U.S. Bureau of Mines and the Alabama Power Company, at the suggestion of the Power Company. The test was conducted on property of the Alabama Power Company, that owns some 19,000 acres of coal-bearing lands on which there is developed a highly mechanized mine producing some 2,500 cons of good quality steam coal per day. At the same locality ?there is a 200,000 kilowatt steam plant one of the largest in the southern portion of the United States. The Alabama Power Company owes much of its beginning in 1912 to British vision and courage. The original plans for building hydroelectric plants in Alabama, and for the construction of necessary transmission lines, were submitted to Sperling & Company, bankers of London, who agreed to underwrite certain bond issues, the proceeds of which would be used in launching the new Company on its programme. The set-up by which these funds from England were received was through an intermediary Canadian company, which the English investors desired. The Canadian company - Alabama Traction, Light and Power Company, Ltd. became owner of the securities of the Alabama Power Company and marketed its own securities through the banking house of Sperling & Company. Without assistance at this time the Alabama Power Company could not have gone ahead with its programme of expansion and the bringing together of the properties necessary for laying the foundation for a strong Company, fortified with ample power resources essential for future requirements and for dependable service to the public.

Jan 1, 1948

By W. C. Holliman

This report on the characteristics of commercial aviation gasolines presents compilations of inspection test data furnished on their products by manufacturers of commercial grades of aviation gasoline, and special data obtained in Bureau of Mines laboratories on samples of these gasolines. Data and physical samples for the survey were submitted by 15 manufacturers on 18 grade 80, 21 grade 91/98, 22 grade 100/130, and 10 grade 115/145 aviation fuels.

Jan 1, 1948

By R. R. Rogers

Abstract The degree of cathodic protection of steel and the anode corrosion rate were determined when anodes and waters of different compositions were used at temperatures similar to those in domestic hot water tanks. Twenty different anode materials, sixteen of them magnesium-zinc-aluminium alloys, were immersed in six different synthetic waters resembling those to be found in various parts of Canada. The results showed that (1) both the degree of cathode protection and the average anode corrosion rate are affected materially by the composition of the anode material and of the water; (2) poor cathode protection is associated with low anode corrosion rate; (3) when the cathode is fully protected, the anode corrosion rate may be comparatively low or comparatively high, depending upon the composttion of the water; (4) an important relationship exists between the magnesium content of the preferred anode and the composition of the water; (5) the degree of protection is increased as the SO4 + Cl concentration of the water is increased and thus as its specific resistance is decreased. Introduction Fairly recently, the use of the active metal magnesium for the cathodic protection of less active metals has received a considerable amount of attention. This interest has been stimulated by the fact that the wartime demand for magnesium was greatly in excess of the present peacetime demand and there is a natural desire to continue operating the large magnesium plants which were built during the war. Information regarding the use of zinc and aluminium for this purpose also has been published. There is a great demand for domestic hot-water tanks which will resist corrosion satisfactorily. This problem is rather complex in view of the fact that the composition of the water used in such tanks varies greatly and depends upon the locality. The present investigation deals with the effect of water composition and anode composition on the cathodic protection of steel under conditions approaching those which exist in hot water tanks.

Jan 1, 1948