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By Henry M. Howe

Jan 1, 1909

By J. E. Howard

On Aug. 25, 1911, a rail failed on the Lehigh Valley Railroad, causing a disastrous wreck. The surface of the fracture was in a plane at right angles to the length of the rail. There was a dark-colored, oval spot on this surface, located on the gage side of the head, representing the part of the rail which was the first to fracture. The nucleus of this spot showed that the fracture had an interior origin. Other fractures of this kind, the peripheries of which had not reached the surface of the rail, presented surfaces having a (silvery luster. The darkened surface of the present fracture was caused, doubtless, by the air having had access to it. This fracture was recognized as a fatigue fracture, of a modified type, its interior origin having been due to a component in the rail which is not usually present in cases of fatigue fractures. The metal next the running surface of the head of the rail was in a state of internal compression, this being the component not commonly met with in other cases, and which caused the fracture to have its interior origin. For the purpose of giving this modified type of fatigue fracture a specific name, for identification, the term "transverse fissure" was applied. No mystery was thought to attach to its formation, or to its development. The explanation of its occurrence seemed obvious in the light of common knowledge upon the behavior of steel under repeated alternate stresses.' By reason of the state of internal compression at the running surface, the maximum tensile stresses in the head, ander bending loads, were along an interior element. Here the tensile strains were higher than in the fibers more remote from the neutral axis. Under such conditions the fracture of the rail would be expected to have an interior origin. A discussion of the subject of transverse fissures essentially becomes a discussion of fatigue fractures, since they are believed to be identical. The descriptive term employed, merely for the identification of this type of fatigue fracture, had the appearance of creating alarm. Apprehensions arose that a new phenomenon in the physical properties of steel had presented itself, the explanation of which was sought in every

Jan 1, 1918

By John McDonald

THIS report is a continuation of an earlier one with a similar title,1 to which the reader is referred for such details of procedure as do not appear here. A brief summary will be given of the objects and methods of the research at this time. It was pointed out in the previous paper that properties of magnesium alloys, as re-ported by different workers, often differ. This was thought to be due to differences in the preparation of the specimens tested. The ideal way to compare alloys would be to prepare each of them in so many ways that reasonable assurance would exist that the best properties of each alloy had been developed. The alloys would then be com-pared on the basis of these properties. The treatment actually given the alloys of these studies is necessarily a compromise with completeness. Nevertheless, enough treatments have been given so that a con-siderable degree of assurance exists that the properties obtained are representative of the alloy as such, and not merely of the manner in which it was worked and heat-treated.

Jan 1, 1940

By P. T. Chiang

Chemical etching methods for the simultaneous revealing of the tellurium or selenium Phase and the chalcogenide grain boundaries of the alloy systems are given. A tellurium eutectic was found Present in zone-melted ingots. Similarly, a selenium monotectic was present in ingots. In general, the second phase (tellurium or seleniumn) occubies three different sites; viz., along the chalcogenide grain boundaries, as inclusions within the chalcogenide grain, and on the undersurface of the ingot. The detection limit for the tellurium phase is about 1 u in width. THERMOELECTRIC materials based on Group V (bismuth, antimony) and Group VI (selenium, tellurium) elements have aroused considerable interest in recent years in the practical application of thermoelectric cooling. In many cases, a small amount of excess tellurium (or selenium) was added to the material to optimize its thermoelectric properties. Then the question immediately arises as to the number of phases present in the resultant alloy. In the binary systems of Bi-Te, Sb-Te, and Bi-Se, the congruent melting compositions have been reported to be non-stoichiometric and are represented by Bi~Te respectively. It is to beexpected and known that Bi2Te3 and SbzTe3 crystallize from the melt with an excess of bismuth and antimony in the lattice and that tellurium forms a eutectic.~' The same could be assumed to take place in the pseudo binary systems of (Bi,Sb)zTe3 and Bi2(Se,Te)3 as well as in the system studiedby puotinen5 and other workers. Likewise, BiaSe3 crystallizes from the melt with an excess of bismuth in the lattice and selenium forms a monotectic.~ Therefore, in practice, alloys solidified from the melt often contain a second phase (tellurium or selenium) in one region or another of the solid mass even without the addition of excess tellurium (or selenium). ~u~~recht' studied the thermoelectric properties of (Bi,Sb)2Te3 alloys with excess tellurium and simultaneous additions of selenium. He mentioned that the materials show two phases because of the considerable excess of tellurium or selenium. However, he did not report as to how the tellurium or selenium phase was identified. It is generally believed that the presence of an excessive amount of tellurium or selenium phase in the alloy would adversely affect its thermoelectric properties and its uniformity. Consequently, there is a need for a simple method for the identification of the tellurium and selenium phase. The quantity of the second phase present is usually too small to be detected either by chemical analysis or by normal X-ray techniques. This investigation was therefore carried out, first, to devise a simple metallographic method for the identification of the tellurium or selenium phase coexisting with the chalcogenides and, second, to determine the distribution and specific location of the tellurium or selenium phase in the ingots. EXPERIMENTAL PROCEDURE The starting materials used for the alloy preparations were 99.999 pct pure bismuth, antimony, and tellurium and 99.997 pct pure selenium. The bismuth and antimony were obtained from Consolidated Mining and Smelting Co. of Canada Ltd., while the selenium and tellurium were obtained from Canadian Copper Refiners Ltd. The tellurium was purified further in the laboratory by zone refining. The elements were pulverized in a stainless-steel pestle and mortar. The amounts for the desired composition were weighed out each time on an analytical balance to make up a 100-g sample. Then the sample was introduced into a Vycor ampule (19 by 150 mm), pumped down to a vacuum of 10"5 Torr for 15 min, and sealed off. The ampule was then heated in a horizontal resistance furnace at 800" to 900°C for about 20 hr. During this period the assembly was rocked back and forth several times to ensure good mixing. At the end of the heating period, the ampule was quenched in cold water and then transferred to the zone-melting apparatus described in a previous publications to grow large-size aligned polycrystals. The background and ring-heater temperatures were adjusted to make the freezing solid-liquid interface slightly convex to the liquid. The recorded temperature gradient in the vicinity of the freezing solid-liquid interface was around 15°C per cm. The ampule was moved horizontally at a speed varying from 0.4 to 2 cm per hr so that the ring heater would cover the whole ingot length from end to end. A single zone-melting pass was used for the Bi-Te, Sb-Te, and Bi-Sb-Te ingots. Two passes in the forward and reverse directions were carried out for the Bi-Se and Bi-Se-Te ingots. Six passes in the forward and reverse directions were performed for the Bi-Sb-Se-Te ingot. The zone-melted ingots were found to contain several large crystals, with their basal planes (0001) approximately parallel to the growth axis. Samples of bismuth and antimony tellurides coated with a layer of tellurium, and bismuth selenide coated with a layer of selenium, were prepared for comparison in phase identification. These coatings were made by dropping a piece of the zone-melted ingot into some molten tellurium or selenium under argon atmosphere and allowing them to cool slowly to room temperature. The metallographic specimens were prepared by

Jan 1, 1969

By J. E. McConnell

No. 1 Electric Furnace and Billet Casting Shop, located in Plant No. 4 adjacent to our new 12 inch merchant bar mill, represents Inland Steel Company's first venture into both electric furnace steelmaking and continuous casting. Construction of the shop began in September, 1968 with excavation and foundation work, followed by awarding of general construction and major equipment contracts from December, 1968 to April, 1969. The first heat was tapped from No. 90 furnace on December 18, 1970, and the first cast attempted on December 29, 1970. The rated shop capacity is 500,000 tons per year of semi-finished billets and blooms, and was justified on the basis of approximately 85 percent of the product mix falling into the special bar quality category of steel grades. Auxiliary equipment has been designed into the shop to pursue free machining steels, including leaded and tellurized grades. The start-up and operation of the shop for the first year was essentially based on a two-part philosophy: 1. Initially operate with the "open stream" casting technique to accomplish machine shakedown and operator familiarization and training. 2. Operate with special bar quality, or "submerged casting", practices, make necessary refinements and gain customer acceptance

Jan 1, 1972

By John Norton

THE tremendous increase in the use of metals that have been prepared by the various cold-working processes during recent years has greatly stimulated the investigation of problems concerned with the fundamental nature of these processes. It has been observed in practice that different methods of bringing about the same dimension changes in a sample result in a rather wide range of properties. Cold working reduces the ductility of a metal, or what is perhaps more nearly correct, its "working capacity," and naturally the manufacturer wishes to produce an article that has as large a working capacity as possible, and to produce it with the smallest number of operations, It has also been known for some time that cold deformation produces a parallel alignment of the crystal grains of a metal, and that the type of this preferred orientation depends to some extent at least upon particular processes employed in the deformation. The present investigation has for its purpose the study of the relations between the various factors of a cold-working process and the preferred orientation of the metal crystals resulting from this deformation. The work is chiefly confined to a study of cold-drawn seamless tubing.

Jan 1, 1932

By Terkel Rosenqvist

Few subjects in iron metallurgy and steelmaking have caused so much discussion and have resulted in so many divergent and partly contradictory statements as the theory of the distribution of sulphur between molten iron and slag. An interesting survey of the different points of view is given by Grant and Chipman.1 Grant and Chipman themselves conclude in their paper that, at least in the open hearth and electric steel furnaces, the governing reaction is a simple distribution like: FeS steel ? FeS alas [Ia] and MnS steel ? MnS alas [Ib] They conclude that no significant reaction takes place according to the more classical scheme: FeS steel + CaO slag ? FeOslag + CaS slag [2a] This is the reaction which is regarded by most investigators as the primary sulphur reaction in the blast furnaces, where it is accompanied by the reaction with carbon: FeO slag + C ? Fe + CO [2b] The writer suggests an alternative to the reactions mentioned above. It is the opinion of the writer that the a priori assumption of defined molecular compounds being present in molten steel as well as in molten slag, has retarded rather than promoted a solution of the sulphur problem. As for the constituents of molten steel, it is taking too much for granted to mention the presence of FeS and MnS. If this infers that the melt contains diatomic molecules, the statement must be made that at least such molecules do not exist in the solid state at room temperature. Solid FeS crystallizes in the nickel-arsenide structure, and MnS (high temperature form) in the sodium-chloride structure. In these structures the sulphur is surrounded by six metal neighbors, and no molecular groups can be isolated. When sulphur is dissolved in molten steel, it is expected to maintain the same coordination number as in the solid state. We know that sulphur in steel has a certain chemical potential and a chemical activity which can be expressed by the reaction: S steel + H2 ? H2S where the activity A. is proportional to the ratio PH2S/Ph2. We know also that this activity is influenced by the presence of other constituents. For instance, there is reason to assume that carbon and silicon increase the sulphur activity and manganese decreases it. However, the exact relationship here is scarcely known, and further investigations are needed. Concerning the molten slags, if anything should be assumed a priori it would be that they are composed of ionic rather than molecular parts. There are indications of this in that solid silicates form ionic structures, and molten slags show high electric conductivity and can be electrolyzed.2 It has been claimed by Taylor and Chipman3 that their activity investigations

Jan 1, 1949

By Terkel Rosenqvist

Few subjects in iron metallurgy and steelmaking have caused so much discussion and have resulted in so many divergent and partly contradictory statements as the theory of the distribution of sulphur between molten iron and slag. An interesting survey of the different points of view is given by Grant and Chipman.1 Grant and Chipman themselves conclude in their paper that, at least in the open hearth and electric steel furnaces, the governing reaction is a simple distribution like: FeS steel ? FeS alas [Ia] and MnS steel ? MnS alas [Ib] They conclude that no significant reaction takes place according to the more classical scheme: FeS steel + CaO slag ? FeOslag + CaS slag [2a] This is the reaction which is regarded by most investigators as the primary sulphur reaction in the blast furnaces, where it is accompanied by the reaction with carbon: FeO slag + C ? Fe + CO [2b] The writer suggests an alternative to the reactions mentioned above. It is the opinion of the writer that the a priori assumption of defined molecular compounds being present in molten steel as well as in molten slag, has retarded rather than promoted a solution of the sulphur problem. As for the constituents of molten steel, it is taking too much for granted to mention the presence of FeS and MnS. If this infers that the melt contains diatomic molecules, the statement must be made that at least such molecules do not exist in the solid state at room temperature. Solid FeS crystallizes in the nickel-arsenide structure, and MnS (high temperature form) in the sodium-chloride structure. In these structures the sulphur is surrounded by six metal neighbors, and no molecular groups can be isolated. When sulphur is dissolved in molten steel, it is expected to maintain the same coordination number as in the solid state. We know that sulphur in steel has a certain chemical potential and a chemical activity which can be expressed by the reaction: S steel + H2 ? H2S where the activity A. is proportional to the ratio PH2S/Ph2. We know also that this activity is influenced by the presence of other constituents. For instance, there is reason to assume that carbon and silicon increase the sulphur activity and manganese decreases it. However, the exact relationship here is scarcely known, and further investigations are needed. Concerning the molten slags, if anything should be assumed a priori it would be that they are composed of ionic rather than molecular parts. There are indications of this in that solid silicates form ionic structures, and molten slags show high electric conductivity and can be electrolyzed.2 It has been claimed by Taylor and Chipman3 that their activity investigations

Jan 1, 1949

A. Blainey (Ministry of Supply, Atomic Energy Research Establishment. Hnrtoell. England)—With ref- erence to the published work of Hausner et al. on the powder metallurgy of zirconium, it will be of interest to summarize briefly the results of preliminary work we have carried out on this subject at A.E.R.E., Harwell. For the early experiments we used zirconium

Jan 1, 1953

By James Douglas

IN discussing the waste upon which hinges, or is supposed to hinge, so largely the preservation of our national resources, the conclusions reached would be more reliable if actual ex¬perience were consulted, and fewer deductions were drawn from general statements, which are often the product of the imagination. It cannot be questioned that the value of by-products has not been sufficiently appreciated by us, and that our, tardiness in recovering the useful ingredients of the escaping gas of our coke-ovens is one of the most glaring instances of shortcoming in that direction. And yet even for that sin there is some palliation in the immature condition of affiliated industries. I presume that it is admitted, without argument, that, except under very exceptional conditions, all the elements cannot be recovered from most of the ores or natural products. which we treat. While it is a shame that the by-products from our coke-ovens should be dissipated, Edward W. Parker's report to the U. S. Geological Survey for 1906' supplies a fairly good excuse in justification of this appalling waste. He says (pp. 773 to 774.)

May 1, 1909

By N. F. Fiore, M. F. McGuire

THIS communication describes a series of experiments in which dislocation etch pitting was used to ascertain the depth of damage in crystals which were mechanically polished or which were cut with either a commercial metallographic cut-off wheel,* a com- All specimens were cut from single crystals of American Smelting and Refining Co. 99.999+ pct pure copper which were grown from the melt by the Bridge-man technique. The test specimens were disks, with faces being (111) planes and the disk axis a (111) direction. The disks were annealed in a vacuum of 10-5 Torr for 24 hr at 950°C prior to cutting or polishing and were given a light electropolishing in an ortho-phosphoric acid bath before etch pitting. Both Youngs1 and Livingston's2 reagents were used for etch pitting and the reagents gave identical quantitative results; however Livingston's reagent produced less staining and so all photomicrographs shown are of {111) surfaces etched with this solution. The surface of the annealed crystals showed well-defined subboundaries and a density of dislocations of about 1 X 106 per sq cm excluding those present in subboundaries, Fig. 1. The depth of cold work produced during mechanical polishing was determined after an annealed specimen was mounted in a paraffin holding block to protect it from extraneous damage. The exposed (111) surface was ground on metallographic papers and then polished on billiard cloth through 0.05-p alumina abrasive. It was necessary to remove about 0.3 mm (-0.01 in.) to obtain a structure representative of the annealed sur- face, indicating that the crystal was damaged to this depth during mechanical polishing. The cold work caused by standard cutting methods was measured in another series of tests in which cuts

Jan 1, 1967

By Merlon C. Flemings, Theodoulos Z. Kattamis

Examination was made of the distribution of tnanganese and nickel in colutrrnar dendrites of a cast low-alloy steel; more limited work was corzducted on chromium. Corresponding "segregrction ratios" were calculnted and shown to be relntivelv insensitive to cooling rate (''segregation ratio" is defined (Is the ratio of maximum to minimum concentrations within a volume whose dimensions are the order of the dendrite-arm spacing). Isoconcentratiorl curves were determined by the electron micropvobe and by rt7etallografihic studies on specimens subjected to isothermal-transformation treatments. From construction of isoconcentration curves, morphology of columnar dendrites is descvibed as intermediate between Perfect rodlike and sheetlike morphologies. The study is extended to equiaxed dendrites and it is shown that the strcture of these dendrites is sittlilar in many respects to that of columnar dendrites. On the basis of tlze sheetlike morphology of dendrites, a simple model is pvoposed for calculation of honzogenization kinetics. Results of trzatllevlatical analysis brcsed on this utzodel are given. This analysis relates residual segregation to time at homogenization temperature; it is in agreement with experiment. Calculations are given which show that even for relatively rapidly cooled material (of 1-ine dendrite-artn spacing) treatmets at 1200°C or above are necessary to achieve slgxificant Izomogenization of elenlents other than carbon itz reasonable time (e.g., rnangclnese, nickel). Conlplete homogenization of carbon is obtnined at much lowev tenlperatures (below 870°C). IN dendritic solidification of castings and ingots, solute redistribution during freezing results in mi-crosegregation of most alloy elements. The micro-segregation is such that minimum solute concentrations occur at the center of dendrite arms and maximum concentrations occur between dendrite arms. Residual segregation after subsequent therma1 processing (homogenization) depends on maximum and minimum initial concentration, on the detailed geometry of the isoconcentration surfaces within interdendritic regions, on the diffusion coefficient of the solute, and on time of thermal processing. The objective of this work was to determine, for a low-alloy steel, maximum and minimum concentrations, and the geometry of isoconcentration surfaces, primarily in order to permit calculation of homogenization kinetics. Most of the work reported was conducted on Samples from a unidirectionally solidified, fully columnar ingot. This type of ingot is made by extracting heat during solidification from one face; techniques for accomplishing this have been discussed.' Samples were taken at several locations, up to 5.75 in. from the mold chill face; the bulk of the work was performed on samples at 5.75 in. Alloy cast was, nominally, 0.4 pct C, 1.8 pct Ni, 0.8 pct Cr, 0.7 pct Mn, 0.25 pct Mo, 0.3 pct Si, and the balance iron. Brief study was also made on samples from an ingot which solidified with equiaxed grain structure. SAMPLE PREPARATION AND ANALYSIS Samples for electron-microprobe analysis were incorporated in mounts that included pieces of electrolytic nickel, chromium, and manganese, in order to normalize the intensities of these solutes in the specimens; also, a piece of electrolytic iron was included to measure the background. All specimens were polished in the usual metallographic manner. After the microprobe traces were made, the path was revealed by etching the specimens with picral. All microprobe analyses were made by point counting, integrating for 30 sec. The distance between points was fixed from 2 to 10 p, according to the precision desired in each case, the fineness of the structure, and the concentration gradient existing in a given area. (The distance was chosen 2 to 5 p near the maximum-concentration regions and 5 to 10 p near the minimum concentration.) The "take-off" angle for the A.R.L.-Model No. 21000 microprobe employed was 52.5 deg. Samples for metallographic analysis of isoconcentration curves were prepared by austenitizing at 1540°F for 20 min, quenching to the nose of the TTT curves (1200°F), heat treating isothermally at this temperature for a given time 0, and then quenching to room temperature. Due to concentration gradients existing in a dendritic structure, no transformation will take place for a given time 0 of isothermal heat treatment in the regions where the a.lloy concentration is higher than a given limit. Thus, the dendrite appears limited by an isoconcentration curve and can be made to appear to grow by varying the time of isothermal heat treatment.

Jan 1, 1965

By James J. Bean

Although determining and controlling specific gravity of operating medium in a heavy-media plant manually presents no problem, there are advantages to automatic recording and control. The two installations discussed employ the usual method of measurement. Pneumatic control with band control and reset features is used to regulate dilution water and hence specific gravity. Difficulties have been mechanical in nature and associated with obtaining a proper I sample and maintaining tight air connections in bubble-tube piping:

Jan 1, 1950

By Walter H. Bruckner, George B. Clark

SINCE the end of World War II interest has been increasing in the use of shaped charges in the mining industry and in other industries using explosives for blasting purposes. Shaped charges employ the principle known as the "Munroe effect," which was discovered by Charles E. Munroe more than 50 years ago (in 1888). Details of their design have been explained e1sewhere.l,2,3 Fig I shows the essential features of design of two types of shaped charges (with conical and hemispherical cavities) and a schematic sketch of their action upon detonation. The following discussion deals with the behavior of the metal in the cavity liners when they are subjected to intense pressures exerted when the explosive charge is detonated. Among the conclusions reached in research on shaped explosive charges, the following have been established concerning cavity liners: 1,2 I. The optimum wall thickness of a conical cavity liner is dependent upon the apex angle of the cone as well as on the base diameter of the charge. Acute apex angles require thinner walls for optimum performance and more obtuse angles require thicker walls for the same base diameter. 2. Cones were more effective in forming a penetrating jet when the walls were tapered; i.e., the thickness of the wall of the cone increased from the apex down. 3. The physical and mechanical proper- ties of metals have a marked effect upon their performance as cavity-liner material. Boiling point, ductility, malleability, tensile strength, and hardness are among the properties that influence the effectiveness of a metal used as a cavity liner. Lead, for example, makes a wide, flat crater in steel plates. Aluminum makes a deeper crater than lead, and an aluminum alloy having a high tensile strength makes a deeper hole, but slightly smaller in diameter. Cast iron makes a deep, narrow hole. These findings, together with the following analysis under Metallographic Survey of Slug, offer solutions to many of the problems involved in solving the mechanism of the formation of Munroe jets. It has been fairly well established that cavity liners collapse in a manner similar to that indicated in Fig 2. Conical liners are known to collapse upon themselves while hemispherical liners are believed to turn inside out in the process of jet formation. The first has been definitely proved by recovery of collapsed portions of cones, while liners from partly detonated charges show that hemispheres may turn inside out. Fig 3 shows a sketch of a recovered slug from a 6-in. shaped charge using a 45° cone made of cast iron. (This size of charge drilled holes up to 3 ft in depth in solid granodiorite.)

Jan 1, 1947

By M. R. J. Wyllie, P. F. Southwick

The importance of the so-called "dirty sand" or "conductive solids" problem in electric log interpretation was first stressed in a paper presented in 1949. Since that time the problem has been generally recognized as a most serious one. Several research papers bearing on the theory of the effects of clay contaminants on reservoir rock resistivities have appeared. These papers, while contributing to the theory of the problem, have not offered any practical solution. In the present paper an experimental investigation has been made of the effects of ion-exchange materials on the electrical properties of natural and synthetic porous media. The method used to make synthetic dirty sands is entirely novel and has proved a valuable guide to a better understanding of the properties of dirty sands generally. The effects of ion-exchange materials on both the resistivity and self potential (S.P.) logs have been examined. From the data obtained it has been possible to formulate a simple, practical method whereby electrical logs of dirty sands can be qualitatively interpreted. The method is in all essentials identical to that presently in use for interpreting clean sands. New light has also been thrown on the significance of the term formation factor when it is applied to dirty sands. In 1949 a paper was presented1 which showed that the presence of so-called "conductive solids" introduced considerable complexities into the analysis of the resistivities of dirty sands, i.e., permeable formations containing clay. The reduction of the self potential (S.P.) resulting from the presence of interlaminated shale or interstitial clay in permeable formations has been discussed by Doll.2,3 Noteworthy papers which dilate further upon the effects of shale and clay on the resistivity of permeable formations are those of deWitte,4,5 Berg,6 Wyllie,7 and most recently, Winsauer and McCardell.8 The last authors have endeavored to elucidate the chemistry of the resistivity phenomena in dirty sands in terms of an adsorption hypothesis. Specifically, they attribute the electrolytic conductivity of shales and clays within a permeable formation to an ionic double-layer effect and, for this reason, regard the term "conductive solids" as a misleading one. Some consideration has been given to the effect of dirty sands on the S.P. by Wyllie7 and by McCardell, Winsauer and Williams." Published work to date has cast light only on certain theoretical aspects of the problems created by the presence of clays and shales within permeable formations. One object of this paper is to describe experiments which serve to elucidate further the theory of the dirty sand problem and particularly the significance of the term "formation factor" as applied to dirty

Jan 1, 1955

By J. F. Emig

The Burns Harbor Plant was designed to produce and process large ingots into plate, hot rolled sheet, cold rolled sheet and tin plate. Rimmed ingots, in particular, are poured 96" to 106" high and weigh up to 85,000 lbs. During the latter part of 1970, a quality problem was encountered involving white line "sliver" defects on the surface of cold rolled, low carbon, rimmed steel sheet. Sheets containing these defects are not desirable for exposed automotive items because of the possibility of opening during forming or becoming more apparent after forming. Metallographic work located and identified two basic types of inclusions within the white line defects: (1) complex oxides consisting largely of iron and manganese oxides and (2) scale-type iron oxide. The presence of these oxides strongly suggested that the-white line defects were resulting from an unsound, unclean rim zone.

Jan 1, 1972

By J. R. Morison, M. P. O’Brein, J. W. Johnson, S. A. Schaaf

The force exerted by unbroken surface waves on a cylindrical object, such as a pile, which extends from the bottom upward above the wave crest, is made up of two components, namely: 1. A drag force proportional to the square of the velocity which may be represented by a drag coefficient having substantially the same value as for steady flow, and 2. A virtual mass force proportional to the horizontal component of the accelerative force exerted on the mass of water displaced by the pile. These relationships follow directly from wave theory and have been confirmed by measurements in the Fluid Mechanics Laboratory of the University of California, Berkeley. The maximum force exerted by breakers or incipient breakers is impulsive in nature, reaching a value much greater than that produced by unbroken waves but enduring for only a short time interval. This impulsive force represents the ultimate development of the accelerative force and is produced by the steep wave front and large horizontal acceleration at the front of a breaker. This impulsive force greatly exceed. the drag force computed from the particle velocities of the breaker. The reader is cautioned that these preliminary results are applicable only to single piles without bracing and are likely to be modified somewhat where multiple piles are driven, one within the influence of the other or where multiple piles are connected by submerged bracing. This paper is essentially a preliminary report submitted at this time because of the current importance of wave forces in the design of offshore structures. An extended series of additional experiments is planned for the near future. Theoretical Relationships For the sake of simplicity of treatment, the theory will be developed from the equations for waves of small amplitude. The horizontal displacement of a water particle is described by the equation 2p cosh — (d + z) H L 2pt X =----------------------sin ----- . , (1) 2 2pD T sinh------ L The horizontal component of the orbital velocity is obtained by differentiation with respect to time as 2p cosh — (d + z) pH L 2pt u = ------------------- cos— .... (2) sinh- L The acceleration of the water particles at any position is obtained by again differentiating with respect to time as 2p cosh — (d + z) 9 u -2vH L 2pt -----=----------------------------sin ----- . . (3) 3 t T2 2pd T sinh------ L where H = wave height — ft L = wave length — ft d = still water depth — ft z = depth below the still water measured negatively downward — ft. T = wave period — sec t = time — sec The force exerted on a differential section, dz, in length is pD2 s u pD 1 dF= [CM (p/4) st + Cn/2 u2] dz • • (4) where D = pile diameter — ft p = water mass density — slugs/ft3 C, = coefficient of mass C,, = coefficient of drag Substituting for a s u/s t arid u2 from Eqs. (3) and (2), the force per unit length at any position z is dF p2 pD H2 &apos; / = — [- fM sin ? ± fD cos2 ? ] . . . (5) dz 2T2 fM D fD 2pt Cm = pA/H:CD = A2;? = T [+ cos2 ? for 0 < ? < p/2 cosh— (d+z) 3p L — < o < 2p Sin L -cos2 ? for p/2 <? <3p/2 The sin 9 term (inertia) i- negative for 0 < 0 < p and positive for p < ? < 2p. Values of A and A&apos; appear in Fig. 1

Jan 1, 1950

By R. T. O’Brien, J. M. W. Mackenzie

A microelectrophoresis technique has been used to measure the zeta potential of quartz over a range of pH and Ni (11) and Co (Ilj concentrations. Results have been discussed in terms of adsorption of Ni (11) and Co (11) cations and hydroxide precipitates. Possible relationships between the experimental results and the formation of lateritic nickel deposits have been discussed. The adsorption of metallic cations to the surface of silicate minerals is of significance in many industrial and natural processes. In an earlier publication,&apos; the adsorption of Fe (111) to the quartz surface, a phenomenon of importance in flotation, was studied qualitatively using microelectrophoresis techniques. This paper reports the extension of this work to an investigation of the adsorption from aqueous solution of Co (11) and Ni (11) to the quartz surface. The adsorption of these metals was of interest for two reasons; firstly, the importance of such an adsorption process in the formation of nickel deposits by the lateritization of nickeliferous rocks, and secondly, the comparison of electrophoresis data for these metals, whose hydroxides precipitate in the pH range 7-8, with similar data for Fe (111) where the hydroxide first precipitates at pH 2.8. The development of laterites is essentially a near-surface geological process involving vertical and, in part, horizontal redistribution of elements derived from rock-forming minerals. This redistribution of elements leads to the formation of layers within the lateritic profile which are enriched in one or more of these elements and, depending on the nature of the original rocks, continued lateritization may give rise to iron ores, bauxites or nickeliferous laterites. The mechanisms discussed in this paper deal with the last mentioned type of deposit although the considered factors are applicable to laterites in general. Nickeliferous laterites are derived from basic and ultrabasic rocks containing ferro-magnesian silicates. These rocks may be partly or wholly converted to serpentinites. Besides their high Mg, Si and Fe contents, they also contain small amounts of Mn, Al, Cr, Ni, Co, Cu and Zn. The nickel content is usually near to 0.2-0.3%, but for economic use this must be increased during lateritization to over 1% and preferably over 2%. The zone of nickel enrichment is usually at some depth within the lateritic profile. Unpublished work by Mr. O&apos;Brien on nickel-bearing laterites in eastern Australia indicated four visually different types of material which were separated from crushed samples under a stereo-microscope. Although chemical analyses indicated that all four types of fragments contained 2-4% nickel and smaller amounts of cobalt, X-ray diffraction and optical studies revealed only quartz, hematite and chromite as well as, in one of the types, a serpentine mineral. No distinct, nickeliferous minerals were detected. Furthermore, it was possible to extract some 60% of the nickel content of the laterites with cold 0.5N hydrochloric acid. It was therefore postulated that much of the contained nickel was present as amorphous, adsorbed material. In considering this fact, as well as the problem of the actual method of transfer and fixation of elements within the lateritic profile, it was further postulated that the transfer of these elements probably took place partly as solutions and partly as colloids and that the fixation of these was caused by adsorption and flocculation. The existence of nickel in solution in water draining from serpentinites has been confirmed by Smurov.2 Although we have no evidence for the transportation of nickel in the colloidal state, it is well accepted that colloids are important in the formation of laterites. Previous work by Mr. Mackenzie&apos; has already indicated that iron may be adsorbed on quartz under conditions which could be expected in a lateritic profile, but no information was available for nickel or cobalt. Although adsorption possibly also takes place on minerals other than quartz, the latter is significant because silica is an important constituent of the silicate parent rocks. During lateritization, it is released to form free quartz and it is likely that it is initially extremely fine-grained. This would provide abundant opportunities for adsorption and it was de-

Jan 1, 1970

By H. Margolin, E. Ence

In order to understand the effect of zirconium on properties of Ti-Cu-A1 alloys, Ti-Zr alloys were examined for the presence of ordering or compounds at the following compositions in weight percent: 24.1 pct Zr (lZr:GTi), 32.2 pct Zr (lZr:4Ti), 38.8 pct Zr (lZr:3Ti), 49.0 pct Zr(1Zr:ZTi). Alloys were prepared as 15-g buttons by non- consumable arc melting under argon atmosphere from Bureau of Mines titanium (Bhn 63) and Reactor Grade zirconium (Bhn 150). Weight losses during melting did not exceed 1 pct of the initial button weight. Prior to heat treatment, buttons were hot-rolled at 600" to 700°C to rods of about 6 mm diam. Contamination after hot-rolling was found to extend to a depth of less than 0.5 mm. Specimens for heat treatment were wrapped in molybdenum sheet, annealed in argon-filled quartz capsules, and quenched by breaking the capsules under iced brine. Annealing times were as follows: 700°C — 7 days; 600°C— 14 days; 575°C-1 and 2 months; 525°C-2 months; 500°C-2 months. Prior to heat treatment, all Ti-Zr alloys were vacuum annealed at 900°C to remove hydrogen. The reanneal of 575°C specimens for an additional month produced no observable microstructure changes. The results obtained by microstructure and X-ray diffraction are shown in Fig. 1, together with data of Hayes et al.&apos; No other phases than a or P were found. Small amounts of retained P were detected by X-ray in the 49 pct Zr alloy. The data of the present investigation suggests that ß and a transus boundaries are at considerably lower temperatures than those of Hayes et al. The work of Hayes et al. is based on sponge titanium and Bureau of Mines zirconium, both of which contained 0.15 pct 0. Since melting was performed in

Jan 1, 1962

By O. J. Hollister

Jan 1, 1888