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By John D. Bradley

Stibnite is 76 miles east of Cascade, Idaho, which is 78 miles due north of Boise. The altitude at Stibnite is 6,500 feet, and between Cascade and Stibnite the Forest Service road crosses two summits - Big Creek at 6,800 feet and Warm Lake at 7,300 feet. The ownership of most of the Meadow Creek group of 190 claims, which is optioned by the Bradley Mining Co from the United Mercury Mines Co. may be traced back from their consolidation by the United Mercury Co. through ownership by prospectors and small promotional companies to the discovery of the Thunder Mountain district in 1900 by the Caswell brothers.

Jan 1, 1942

By J. W. Thompson

SALE AND CONVEYANCE. DEED BY INDIAN ALLOTTEE OF UNSOUND MIND-BONA FIDE PURCHASER. The deed of an Indian allottee whose mind was unsound, but who was not entirely without understanding, is voidable if made before the grantor's incapacity has been judicially determined; and a purchaser of the original grantee who interposes the defense of a bona fide purchaser has the burden of showing a purchase for value and on failure to do so can not claim the benefit of a bona fide purchaser. Adams Oil & Gas Co. v. Hudson (Oklahoma), 155 Pacific, 220, February. 1916. PURCHASER OF MINING CLAIM-RIGHT TO FIXTURES. The purchaser of a mine equipped with an electric hoist, placed in the mine under a rental contract with the owner of the hoist and under an agreement to return it to the owner at the expiration of the term of hiring, can not claim and hold the hoist as against the owner where the agent of the seller explained to the purchaser that the hoist was not owned by the owner of the claim. Montana Electric Co. v. Northern Valley Mining Co. (Montana), 153 Pacific, 1017. p, 1018, October, 1915. AUTHORITY OF GRANTEE TO EXTEND LEASE. A deed conveying lands subject to an oil and gas lease under which the lessee had the right to drill or pay money in lieu of drilling at his option, and reserving to the grantor a share of the royalties under such lease, and expressly authorizing the grantee to lease the land for oil and gas purposes and to take the rentals, authorizes the grantee to extend the existing lease before the expiration thereof in consideration of the annual payment of money in lieu of drilling, as contemplated by the lease.

Jan 1, 1916

By B. W. Zhao

Quantitative analysis of minerals composing in ore is primary in process mineralogy, a veracious quantification and analysis is very crucial to optimize or design a beneficiation process, especially for a low grade and complicated ore. This paper will discuss a SEM-EDS based quantitative analysis developed in JKtech Australia through an example from Jinchuan lean ore. For a low grade, com-plex intergrowths and texture lean ore, chemical phase analysis of value minerals and identification by optical microscope are very essential, unite the SEM-EDS based quantitative analysis, we can understand exactly the lean ore, explain and quantify the process performance.

Jan 1, 2014

By Yuchen Wu, Purushotham Thkkaraja, Marek Borowski, Jie Liu, Jianwei Cheng, WANCHENG ZHENG, Yu Wang, Weidong Lu, Gang Zhao, Zhanyou Sa, Huan Yang, Yuhang Wu, Hui Wang

The abstract discusses the importance of gas drainage in coal mines for safety, environmental protection, and resource utilization. It highlights the significance of borehole sealing technology for efficient gas drainage. The study introduces a new inorganic retarding sealing material and investigates its properties, including stability, thermal stability, fluidity, and thixotropy. The material's diffusion performance in cracks is tested using a self-designed system. Field tests in a coal mine demonstrate the material's effectiveness in improving borehole sealing compared to traditional materials.

May 1, 2022

By S. Saha

Minerals in coals cause operational problems in various coal utilization technology as well as act as diluents towards its heat value. Indian coals contain higher percentage of mineral matter compared to foreign coals due to its formation through drift origin. Efficient utilization of high ash coal in environment friendly manner is the driving force for the development of clean coal technology. Coal gasification offers practical means meeting stringent environment controlled parameters for producing power, chemicals, liquid fuels and clean energy on a single platform. It is well accepted that gasification technology has sufficient potential for sustainable development of clean coal technology. Gasification reactivity depends on the coal properties and operational parameters as well as minerals present in coal. Minerals not only create operational problems but on the other side also catalyze the gasification and combustion reaction. Therefore to understand the effect of minerals on the gasification reactivity, present paper proposes to study the variation of gasification reactivity with various gravity cuts such as, 1.4-1.5; 1.6-1.7; and 1.8-1.9 of a selected coal. Gasification reactivity has been studied by thermo gravimetric analyzer (TGA) using CO2 as gasifying agent. Surface properties such as, true density, apparent density, porosity, surface area of different gravity cut samples have also been measured to find out the effect of gravity separation on gasification reactivity. Keywords: gasification, reactivity, mineral matter, gravity separation

Sep 1, 2012

By D. A. Reynolds, C. R. Holmes

The Bureau of Mines - American Gas Association ( EM - AGA) carbonization test has been used to determine the carbonizing properties of 66 American coals and a larger number of coal blends . A summary of the results obtained for the first 30 coals , including 6 blends , has been published ,4/ and results for individual coals have been reported as the investigations were completed . A bibliography of all publications pertaining to this work has been issued recently . Many of the coals were carbonized at 800 ° and 900° C. in two sizes of retorts ( 13- and 18 - inch diameters ) ; and , because the quality of coke is affected by changing the size of the retort , this report has been prepared to show the average physical properties of coke from the two sizes . This report also purposes to extend the correlation of the physical properties of coke with the rank of coal made by Fieldner and Davis in their summary of the EM-AGA tests on the first 30 coals .

Jun 1, 1942

By J. C. Stankus

Many coal seams are associated with soft floor strata and during mine development if coal pillars are not properly designed, floor heave occurs and causes interruption of coal production. In the severe cases, the section or mine is abandoned. One of the methods for controlling floor heave is floor bolting. This paper describes the demonstration of floor bolting methods in a West Virginia coal mine. Three methods were used: (1) vertical full resin bolting, (2) floor truss bolting, and (3) floor truss bolting plus a floor cut at the center of the entry. The design of each method and the experimental results are discussed in detail.

Jan 1, 1993

By Bruna Helena Malovini Loiola

Os aços ligados ao níquel especificados pela norma ASTM A 522 são utilizados na fabricação de válvulas, flanges e conexões de tubos, na indústria automotiva, na construção civil e na área naval. Na indústria de petróleo e gás, o material requer desempenho adequado para resistir às altas pressões, ao ambiente corrosivo e à abrasão. Considerando os efeitos do desgaste nas válvulas e flanges, este trabalho tem como objetivo avaliar o efeito da temperatura de revenimento na microestrutura e dureza do aço. Amostras submetidas à têmpera a 860°C e ao revenimento na faixa de 380 a 630°C proporcionaram resultados que mostram uma microestrutura predominante de bainita após têmpera e redução da dureza com o aumento da temperatura de revenimento devido ao alívio de tensão.

Aug 17, 2017

By A. Raman, P. P. Singh

The constitution of the La-Rh system was studied by powder X-ray diffraction, metallopaphic, and differential thermal analysis techniques and an equilibrium diagram is presented. Eleven intermediate phases occur in the system and the crystal structural data for nine of them were determined. La3Rh crystallizes in an orthorhombic structure of undetermined type, whose unit cell is obtained by doubling the 'a; and 'c,,' edges of an FesC type unit cell. The other intermediate phases of the system are LarRh-3( undetermined structures also occur in the system. LaRh, undergoes a polymorphic phase transformation at 1240°C. LaRh3 and La2Rh7 also exhibit polymorphisnz. The phases Laah and LazRh7 melt congruently. The latter undergoes a eutectoid transformation into LaRh, and Rh at 1205°C. Laah3 is formed by a peritectoid reaction between Laah and La,Rh,,. The other Phases result from peritectic reactions between the liquid and the adjacent rhodium-rich phases. The intermediate Phases of the La-Rh system are compared with those of the La-Co and La-Ni systems. DURING the course of a detailed investigation to study the occurrence of CrB, FeB, A1B2, and related structures in the rare earth alloys it was found that much information is lacking for the rare earth noble metal systems. Although the structures of several rare earth alloys containing the noble metals at the AB and AB2 stoichiometries have been reported, the occurrence of related structures at other stoichiometries has not been studied. We have initiated a project to study the crystal structural features of selected rare earth-rhodium alloys and to map the equilibrium diagrams of representative systems with conventional methods. The results of our investigation in the La-Rh system are presented in this paper. Two phases were known in the La-Rh system. LaRh has the CrB-type structure.' LaRhz is a MgCu2-type Laves phase.z EXPERIMENTAL PROCEDURE Alloys weighing less than 1 g were prepared from commercially pure lanthanum (99.9 pct +), supplied by Lunex Company, Pleasant Valley, Iowa, and rhodium (99.92 pct +), supplied by Engelhardt Industries, Newark, N.J., in a conventional arc melting furnace under argon atmosphere. The buttons were turned upside down and remelted three times to insure homogeneity in the samples. Since negligible loss of material was encountered during melting, a chemical analysis of the alloy buttons was not undertaken. Powder specimens for X-ray diffraction studies in the as cast state were then prepared. The buttons were wrapped in thin molybdenum foils and homogenized by heating in vacuum at suitable high temperatures for more than 1 week. They were then broken into three or four pieces for annealing experiments. The pieces were wrapped in molybdenum foils and annealed at various temperatures in evacuated quartz capsules. The annealing was carried out for 2 hr at or above 1200°C, 1 day at temperatures close to llOO°C, 2 days at 1000°C, and for 1 week at temperatures below 1000°C. After annealing the alloy pieces were again broken and powder specimens for X-ray diffraction were prepared. The powders of the lanthanum rich alloys with more than 80 at. pct La were prepared by filing. The filings were sealed in molybdenum tubings and stress-relieved at 600°C in vacuum. It was not deemed necessary to stress-relieve the powders of the other alloys, since the alloys were very brittle and were ground easily. POWDER X-RAY DIFFRACTION X-ray diffraction photographs of powders (-325 mesh size) of the alloys in the as cast and annealed states were prepared in a Guinier-de Wolff focussing camera with copper K, X radiations. These patterns were studied to identify the stoichiometries and the crystal structures of the intermediate phases. The lattice parameters of the phases were calculated after minimizing the differences between the observed sin2 6 values, calculated from the diffraction angles 8, and the sin2 8 values, calculated using approximate lattice constants obtained from a few lines. These differences were minimized manually to less than 0.0005. The latLice constants are judged to be accurate to *0.005A for values less thp about 10A and to k0.01~ for values greater than 10A. The relative intensities of the lines were calculated using a computer program written by Jeitschko and Parthk.~ No attempt was made to refine the atomic positional parameters in the phases. METALLOGRAPHY The phase equilibria in the investigated alloys in the as cast and annealed states were also studied by metallographic examination. The polished specimen surfaces were etched with 10 pct picric acid in alcohol (alloys up to 25 pct Rh), concentrated picric acid (from 25 to 37.5 pct Rh), 2 pct nital (40 to 50 pct Rh), 10 pct nital (from 50 to 66.7 pct Rh) and with concentrated 48 pct HF for the other rhodium-rich alloys. Selected microstruture~ were then photographed using a Po-laroid Land camera. THERMAL ANALYSIS Differential thermal analysis of the alloys was carried out in DTA-668 Stone differential thermal ana-

Jan 1, 1970

By G. van Eck, H. Smit, L. Meyer

The Cook Islands (CI) possesses within its Exclusive Economic Zone (EEZ) a massive field of polymetallic nodules representing one of the world’s largest undeveloped cobalt deposits, along with large quantities of other metals critical to achieving global energy transition targets. In February of 2022 the Seabed Minerals Authority (SBMA) of the CI granted Moana Minerals a license to conduct our nodule exploration program. This paper describes how Moana Minerals chose to approach conducting exploration activities, one of the greatest challenges to Deep Sea Mining (DSM) development and the securing of the social license to advance to eventual mining of the resources, in an unconventional manner. The remote location of the project poses logistical challenges in mobilizing to and operating in the region and is a significant cost driver. Historically, exploration campaigns mobilized large vessels from mainland Europe, the Americas, and Asia as this model works well when contemplating long duration and widely temporally spaced campaigns without the need to revisit. Moana Minerals, when considering these challenges determined a multi-year deep sea mining (DSM) exploration program conducted in such a remote location can be better optimized by the deployment of a smaller yet highly capable “exploration optimized” vessel that is dedicated to the task and is based full time in the Cook Islands. INTRODUCTION The paper describes the challenges of exploration in remote regions including the South Pacific, and how an unconventional consideration of the problem led to the solution. Completion of an Environmental and Social Impact Assessment begins with a detailed environmental scoping study, resource update sampling requirements, and engineering data and sample requirements, which identifies the exploration goals of the project and technology needed to accomplish those goals. The method walks the reader through vessel and technology selection, discusses the challenges of equipment selection considering size and capability, describes the final arrangement, and provides results from the initial exploration campaigns. We followed the project from conception through the shipyard conversion, mobilization, and initial operations in the Cook Islands. The result shows how a smaller vessel with limited budget makes a large impact on the exploration capabilities in the region while building public trust. The Anuanua Moana is the first dedicated deep sea minerals exploration vessel modified with a suite of technologies that allow it to compete technically with existing ships but operate locally in the smaller ports of the South Pacific. The unique combination of size and technical capability gives the Anuanua Moana advantages over other vessels. This paper shows the importance of the Anuanua Moana in the development of offshore exploration strategies in the emerging deep sea minerals space.

Feb 22, 2026

By P. M. Tyroler

Inco operates a hydrometallurgical plant to treat the residue from the pressure carbonylation process. The main constituent in the residue is cop¬per. The residue is leached under pressure in an acid sulphate solution in two stages and the copper is recovered via electrowinning. The electrowinning tankhouse is fully integrated into the overall plant flowsheet as spent elect¬rolyte is required in upstream leaching steps. In recent years, the amount of residue had increased and copper removal capacity became the rate limiting factor for the entire plant. Consequently, a major program was undertaken to upgrade the tankhouse with regards to capacity, efficiency, cathode quality, working environment and structual integrity and appearance. This paper will describe current facilities and operation, and detail progress in our up¬grading efforts.

Jan 1, 1987

By Leonard Obert, Wilbur Duvall

"INTRODUCTION 'The investigation reported herein is part of a comprehensive research program being conducted by the Metal Mining Research Section, Mining Division, Bureau of Mines, on pressure problems in underground mines. This program was initiated in 1937 and for the first 3 years was concerned primarily with measurement of the pressure on mine pillars and supports and their strength. 4/ 5/ During this period, investigations were conducted in both the laboratory and the field in the comparatively shallow load and zinc mines of Missouri and Oklahoma. As a result a seismic method of determining the pressure on mine pillars was developed.Before this research program was initiated, Chas. F. Jackson, chief of the Mining Division, suggested that rock under pressure might give rise to noises inaudible to the unaided ear - that is, subaudible noises. As a result of this suggestion, listening tests were made concurrently with the routine pressure measurements to see if any rock noises were present; with one exception, it was found there were no rock noises in any of these shallow mines. At the same time, pressure measurements disclosed that, with one exception, pillars were not under pressure amounting to more than 10 percent of the crushing strength of the rock. The one exception was a pillar in the Big John mine of the Eagle Picher Mining & Smelting Co. in the Tri-State district, which showed some physical evidence of failure, such as small cracks and spalling; it was reported that the pillar had been heard to crack or snap at intervals. Listening tests in this pillar disclosed that subaudible noises of comparatively small intensity were present and occurred at 1- to 2-minute intervals, on the average. Unfortunately, owing to the shortness of this pillar it was impossible to make any pressure measurements."

Jul 1, 1942

By Harry W. Campbell

In 1986 at the request of the U.S. Bureau of Land Management, the U.S. Bureau of Mines studied the 2 acre North Sisters Rocks Wilderness Study Area (OR-12-8) in order to evaluate its identified mineral resources. The Wilderness Study Area is located in Curry County, Oregon, about 15 miles north from Gold Beach. No mines, prospects, or mining claims were located inside the study area, and no mineral resources were identified. Stone from the study area could be quarried and used for construction purposes; however, two nearby quarries have sufficient stone to satisfy local construction needs. INTRODUCTION This report describes the USBM (U.S. Bureau of Mines) portion of a cooperative study with the USGS (U.S. Geological Survey) to evaluate mineral resources and mineral resource potential of the North Sisters Rocks WSA (Wilderness Study Area) 1/ at the request of the BLM (U.S. Bureau of Land Management). The USBM examines individual mines, prospects, claims, and mineralized zones, and evaluates identified mineral and energy resources. The USGS evaluates potential for undiscovered resources based on areal geological, geochemical, and geophysical surveys. Results of investigations will be used to help determine the suitability of the North Sisters Rocks WSA for inclusion into the National Wilderness Preservation System. Although the immediate goal of this and other USBM mineral surveys is to provide data for the President, Congress, government agencies, and the public for land-use decisions, the long-term objective is to ensure the Nation has an adequate and dependable supply of minerals at a reasonable cost.

Jan 1, 1987

By J. F. Burr, D. P. Snyder, G. W. Luxbacher

"The Mine Improvement and New Emergency Response Act (MINER Act) of 2006 (PL 109-236, 2006) established the Office of Mine Safety and Health, functioning as the Office of Mine Safety and Health Research (OMSHR) within the National Institute for Occupational Safety and Health (NIOSH) and provided authority for awarding contracts related to the development and implementation of new mine technology and equipment. The OMSHR external contracts program was formed in accordance with the MINER Act and has since issued more than 150 contracts focused on worker health and safety. Initial funding for this program was provided by the United States Congress through two emergency supplemental appropriations and was focused on emergency oxygen supply, communications and tracking, and refuge chambers (also referred to as refuge alternatives). Since the MINER Act, Congress has continued to fund the program through the annual NIOSH mining appropriation. The program was supplemented starting in 2009 with an academic capacity building program directed toward developing university tenure-track faculty and facilities and supporting graduate students in the area of mine ventilation. Ground control was added as an additional focus area in 2011. A short synopsis of each contract is published on the NIOSH Mining website (www.cdc.gov/niosh/ mining/researchprogram/contracts/index.html) and final reports are available in digital form on request. A summary of the progress OMSHR has made over the 10-year period since the Act was published previously (Snyder et al., 2016).External contracts are broadly classified by the following areas:• Communications and tracking.• Emergency response.o Self-escape and breathing air supply.o Refuge alternatives.o Escape and rescue.• Equipment safety.• Fires and explosions.• Ground control.• Mine environmental systems (mine ventilation and atmospheric monitoring).• Worker/workplace health and safety.Contracts are issued under a request for proposal (RFP), through a broad agency announcement (BAA) or under an interagency agreement (IAA). An RFP solicitation includes a specific problem description and a well-defined scope of work to guide the offeror in preparing a bid to conduct the research. Under the BAA several problem areas are described and the offeror develops the scope of work and deliverables for the proposed research. An IAA is very similar to an RFP except it is a contract between two federal government agencies."

Jan 10, 2018

By Klaus Grebe

Recent investigations by Mannesmann Research have shown that disintegration of sinter with widely varying quality levels is subject to a much more complex set of influences than was previously assumed. It was confirmed that disintegration at temperatures between 300 and 600 °C is triggered by the degradation of hematite. The specific tendency of hematite to disintegrate is, however, not constant: sinters containing the same amount of hematite can show widely differing disintegration tendencies depending upon structural homogeneity, porosity and gangue quantity. Especially sinters with heterogeneous structures transmit stress to the hematite phase and this favours disintegration. Another factor is the brittleness of the glassy silicate phase, which can be influenced even by small modifications of minor gangue constituents.

Jan 1, 1981

Tax for Toxic Waste Cleanup. - The Superfund Act of 1980 became effective April 1, and provides that producers of certain metals and chemical substances are to be taxed in order to fund toxic waste cleanup. Industry will provide 88% of the 5-year, $1.6 billion fund. The Environmental Protection Agency will administer the Act, but the Internal Revenue Service will be responsible for collection of the industry tax. Under the Act, nickel companies, for example, will be required to pay a tax of 0.225 cents per pound on pure nickel products produced or imported into the United States. Standard for Exposure to Lead. - The Occupational Safety and Health Administration (OSPA) has announced a stricter standard on the test of a worker's exposure to lead. Effective May 15, in all lead intensive occupations with the exception of those at primary and secondary lead smelters, a worker would have to be removed from his work station if the level of lead in his blood tests out at 60 micrograms of lead per 100 grams of blood, instead of the previous standard of 70 micrograms. In the case of primary and secondary lead smelters, the ruling has been stayed until June 1, 1981, to allow time for further study.

Jan 1, 1981

By Josh Struble, Fu Yuet, Jan Zywiel, Kevin King

This paper discusses the application of Integrated Inertial/GPS technology for position determination of earthmoving equipment in an open-pit mine. Different GPS augmentation methodologies are introduced and discussed. Principles for the operation of the Applanix POS MC (Position and Orientation System for Machine Control) are also presented, together with test results conducted at the Twin Creeks Newmont mine, using the POS MC and Caterpillar’s CAES (Computer Aided Earthmoving System).

Jan 1, 2005

Sedimentation is used to clarify process effluents or to thicken process slurries. The sedimentation cycle of a suspension is presented as a settling curve. This curve is simply a plot of the height of the interface between the settled suspension and clear liquor versus time. Figure 1 shows a series of graduate cylinders which contain a suspension at various stages in its settling cycle. Cylinder 1 shows the suspension completely mixed at time zero. After a brief period of time (see cylinder 2), the suspension is observed to settle from its initial height Ho to height H1, leaving behind a volume of clear (or turbid) liquor, called the supernatant. The interface between the supernatant and suspension is termed the mud line. It is also possible to distinguish at the bottom of the cylinder a layer of sludge representing solids which have settled from the suspension. The interface between it and the suspension is called the sludge line. The sludge line moves upward in the cylinder.

Jan 1, 1992

By C. S. Smith

The solubility of tantalum at 1100°C is 0.025 pct in pure copper, 1.2 pct with 20 pct Ni, and 2.7 pct with -30 pct Ni. The solubility decreases with temperature, and the alloys are precipitation hardenable. A 79/20/1 Cu-Ni-Ta alloy reaches maximum hardness after aging at about 750°C and, if cold worked, does not recrystal-lize below that temperature. The alloys have good tensile properties at moderately elevated temperatures and, since they can be hot and cold worked nearly as easily as cupronickel, they are suggested for service at temperatures above the usual limits for copper alloys. MASSIVE tantalum dissolves extremely slowly in copper-rich alloys, and tantalum powder forms refractory surface layers which prevent its solution unless special precautions are taken. After many trials, an 80 pit recovery was consistently obtained by using a mixture of a finely divided tantalum powder with two or three times its volume of potassium tantalum fluoride (K2TaF1,-melting point about 750°C) poured in a slow stream directly on to the surface of the molten copper alloy, so that each particle would remain coated with flux and be immediately and individually wetted by the molten metal. A 50-50 nickel-tantalum alloy has a melting point of about 1400°C and small lumps of it slowly but satisfactorily dissolve in molten copper-nickel alloys as does commerical "ferro-tantalum." The high affinity of tantalum for carbon makes it necessary to avoid carbonaceous crucibles. COPPER-TANTALUM ALLOYS Castings with good shrinkage resulted when 0.1 pct Ta or more was added to copper melted under charcoal and cast in air. Copper in two-pound melts to which 0.1, 0.15, and 0.2 pct Ta had been added retained residual amounts, by analysis, of 0.025, 0.023 and 0.026 pct, respectively. The solubility of tantalum in molten copper at about 1200 °C is therefore about 0.025 pct. The electrical conductivity of these three samples was 100.48, 100.00 and 100.20 pct IACS in the annealed condition, and 98.24, 97.98 and 98.08 in the cold-drawn condition. Wires 0.080 in. in diam withstood from thirteen to nineteen reversed bends after annealing for 30 min in hydrogen at 850°C and the metal was therefore completely deoxidized. The annealing temperature corresponding to 50 pct loss of work hardness in 1 hr in a strip cold rolled 77 pct reduction was 175C, compared to 230°C for equivalent undeoxidized material. It is unusual for a decrease of recrystallization temperature to result from an alloying addition, and the tantalum probably combines with and removes some minor impurity in the original copper that restrained its recrystalliza- tion. No difficulty whatever was encountered in hot or cold rolling or drawing these ingots, and were tantalum not so expensive it would make an excellent deoxidizer for copper. COPPER-NIcKEL-TANTALUM ALLOYS Studies were made of the solubility of tantalum in a large number of copper-rich alloys, but of these significant solubilities were found only in the case of an iron alloy (which, however, separated into two immiscible liquid layers) and alloys of copper and nickel, in which tantalum is freely soluble and which were found to have interesting properties. The latter alloys are the subject of U. S. Patent No. 2,430,306 (1947). They are not at present available commercially. The Ternary Constitution Diagram—The copper-rich corner of the constitution diagram was constructed on the basis of microscopic examination of samples of various composition and treatments. The alloys were hot rolled to 0.25 in. from castings 0.625 in. thick, then annealed for 1 hr at 1000°C, quenched, cold rolled to 0.10 in. and finally annealed for various periods of time at temperatures between 800" and 1100°C in a nonoxidizing atmosphere and quenched. When the solid-solubility limit had been transgressed, particles of a compound believed to be Ni2Ta*were

Jan 1, 1960

By Jack R. Woodyard

Bonding angles, promotion energies, and relative atomic sizes can be estimated through the solution of a set of algebraic equations generated from simple atomic models, and quantum mechanical parameters such as bond strength can be estimated from simple, hydrogenic form-wave functions. The precepts of The Engel-Brewer Theory are melded with the "Crystal Approximation Model" to produce atomic-structure models making these predictions, The two-valence-electron case is presented in this report. For the candidate atoms Be, Mg, Ca, Sr, and Ba the calculated promotion energies agreed within a few percent of their experimental values. These atomic parameters determine the possible crystal structure of the candidate atoms when alloyed. This is part of the effort at the U.S. Bureau of Mines to develop methods for alloy design in response to requirements for new high-performance alloys that conserve critical or rare materials.

Jan 1, 2010