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By A. B. Campbell

The Bureau of Mines is developing alloys using ion implantation as an alternative to bulk alloys that consume large quantities of strategic materials such as chromium and nickel. These alloys are formed at the outer layer of relatively common materials. To more fully understand the corrosion characteristics and physical properties of this outer layer, it was necessary to deter-mine the alloy concentration as a function of depth into the substrate material. Also, since many of the ion-implanted alloys would be utilized at elevated temperatures, it was necessary to determine the diffusion behavior of the implanted element. Proton-induced X-ray emission and inert gas ion sputtering have been utilized to generate composition depth profiles for Fe-Cr, Fe-Ni, and Fe-AI ion implanted alloys fabricated by implanting 25-kev Cr+, Ni+, or AI+ into iron substrates. The data were fitted (utilizing a computer program) with symmetrical Gaussian profiles yielding values for the range and range straggle of the ions. These parameters were then compared with those calculated from theory. Changes in the profiles due to annealing were investigated and values for the diffusion coefficient were obtained assuming diffusion according to Fick's Law. For the Cr+ and Ni+ implantation, the profiles as-implanted agree reason-ably well with theory and exhibit ?norrmal" diffusion characteristics at 500° C. For the Al+ implantation, the profile as-implanted is much broader than predicted and exhibits substantial enhanced diffusion at temperatures up to 500° C.

Jan 1, 1979

By Edward F. Courtney

Loss of life, loss of sight, crippling injuries, and property damage nearly always result from accidents involving explosives. The severity of such accidents has prompted lawmaking bodies to pass laws concerning the transportation, handling, and use of explosives; manufacturers of explosives publish manuals 'describing explosives and practical methods of handling then; and mining companies and others who use large quantities of explosives publish rules based on actual experience for the guidance of their employees. Careless storage of explosives by thoughtless or incompetent persons, particularly if they are left where children or saboteurs have access 'to them, has led to many serious accidents. Many contractors and mining operators who use explosives are extremely careless about storing them. It is the purpose of this paper to discuss the explosive-handling practices of a large western mining company, which are considered better than most.

Jan 1, 1946

By Oliver Q. Leone

Three electrorefining cells were designed to investigate various factors associated with the electrorefining of reject - grade titanium sponge . Operation of the cells provided information on cell design as well as on how design and operating variables affected the quality of the titanium product . A sodium chloride - titanium chloride electrolyte was used , and the electrolyte chambers had capacities ranging from 400 to 3,500 pounds of molten salt . Major factors investigated were electrolyte composition , temperature and useful life , effect of various cathode shapes and materials of construction , methods for removing cathode deposits , effect of current density and cell potential , and the mechanics of deposit growth and crystal morphology . One of the cells was in intermittent operation over a 4 - year period and produced 2 tons of refined titanium . A product with a hardness of 80 or less Bhn (Brinell hardness number ) was consistently and easily obtained . Some metal with a hardness of less than 60 Bhn was produced . In one of the cells in which the electrolyte was held at operating temperature with an internal heater an ac input of 25 kw maintained 3,500 pounds of electrolyte at 850 ° C , but with an external heater 35 kw was required to maintain 400 pounds at 850° C.

Jan 1, 1964

By L. B. Pankratzt

The heat content above 298.15° K of ferroelectric lithium columbate (LiCbO3) was measured to 1,770° K. The Curie temperature was determined to be 1,450° K, the melting point 1,540° K, and the heat of fusion 16.94 kcal/mole. Heat content and entropy increments have been tabulated for the temperature range from i98.15° to 1,800° K. Heat contents are also given in equation form.

Jan 1, 1966

By E. J. Matson

"SUMMARYThe Bureau of Mines has been investigating deposits of critical and essential minerals in the United States since 1939. Projects were set up on only the most promising properties. A preliminary examination of the Rio Grande property was made by Bureau of Mines engineers in July 1942 and the property was examined again in July 1943.The Geophysical Branch of the Bureau undertook a Geophysical survey of the area in November 1943 and was intermittently active in the district until June 1946. The major portion of their work was done from June 191 to November 1945. Favorable areas for exploration were recommended by the Geophysical Branch of the Geological Survey, 3/ and all holes were drilled in them.Two projects were set up by the mining branch in an endeavor to find ore bodies on the strength of the geophysical information."

Sep 1, 1947

By Harold B. Ewoldt

The Appalachian Ores Co., Sweetsprings, W. Va. was a small but persistent producer of manganese ore for several years prior to 1942. Most of the ore mined was hard, nodular psilomelane, with some pyrolusite and, wad, occurring in clay. The Bureau of Mines started an investigation of the area in January 1942 and completed the work in May 1942. Twenty-four churn-drill holes were bored, aggregating 2,084 feet. A total of 420 feet of test pits was sunk on selected drill holes to check the churn-drill sampling. Twelve drifts and crosscuts aggregating 139 feet were driven from the bottom of test pits to investigate concentrations of manganese nodules. Three hundred sixty-six churn-drill samples and 102 other samples were sent to Bureau laboratories for analyses. Beneficiation tests were conducted in the Burp.au of Mines laboratory in Rolla, Mo. Results of testing 10 samples indicated that approximately 80 percent of the material in crude ore could be discarded by log washing. Gravity tests indicated 'that 55 percent of the total manganese in the crude ore was recoverable as a gravity concentrate averaging 34.6 percent manganese.

Jan 1, 1949

By C. W. Owings

Available literature published or abstracted in 1953 and 1954 relating to dust prevention and suppression has been summarized and reviewed in this report, and un-published information also is included to outline current practice for those interested in dust control in and around mines, tunnels, and quarries. More and more companies are realizing the value of controlling dust by incorporating suitable methods and devices in the planning stage. In preparation and crushing plants preliminary tests have been made of the fine materials to determine the best type of dust-control equipment to use, and the details of the quantities of air, the number of sprays, the dust-allaying fluids, and the location of hoods or enclosures have been determined in advance. Such planning has paid for itself in more effective control. Similar planning in a tunnel resulted in healthful conditions and low dust concentrations.

Jan 1, 1956

By Lee Blackman

The Malheur-Jordan Resource Areas (MJRA?s) is a tract of approximately 6.5 million acres of federal and non-federal land in the southeast corner of Oregon. This study evaluated the Resource Areas' economically recoverable mineral potential based on geological estimates provided in the USGS report (Smith, 1994). The mineral terranes are believed by geologists to contain undiscovered resources. The geological data is probabilistic; with estimates of the possible number of deposits and their grades and tonnages. Possible future development scenarios range from no development to numerous mines. Based on the analysis performed on these terranes, the most likely (in a statistical sense) future scenario for the resource areas would include the potential for two medium sized, predominately gold, mines. These would supply direct and indirect employment of up to about a thousand workers.

Jan 1, 1995

By G. T. Krempasky

This report covers the installation and evaluation of lb reinforced concrete sets, 6 in each of 3 mines in the Goeur d'Alene mining district, Shoshone County, Idaho, and is the second of a series to determine the feasibility of a more permanent type of mine support. Closure measurements, where applicable, were made periodically of the concrete-set installations and were compared to the initial cross section of the sets. A different method of blocking was used at each test site; at one test site the type of blocking was changed several times during the test. Results from each test site are reported separately. No attempt was made to compare the cost of the concrete installations with the cost of other types of support used in the district. Such an evaluation of permanent types of support would require a longer period of time. At this time, tests are not complete enough to determine the applicability of underground concrete supports. However, results to date tend to confirm the general opinion that precast concrete mine supports could be used to advantage in openings that require support and must have long life, especially where decay of timber is an important factor.

Jan 1, 1963

By Robert E. Barieau

This report gives the principles of the method used by the Helium Research Center of the Bureau of Mines when solving nonlinear-regression problems and contains the mathematical equations necessary to accomplish the following objectives: the evaluation of the parameters in such a way that the sum of the weighted squares of the residuals of an experimental observable is a true minimum, regardless of the functional relationship between the variables and these parameters; and the evaluation of all variances and covariances of the parameters by means of the usual approximation of the law for the propagation of errors.

Jan 1, 1967

By A. L. Engel

The Bagdad-Chase copper-gold mine south of Ludlow, Calif., was visited by an engineer of the Bureau of Mines in July 1955 to determine the mine's status of activity and to obtain a bulk sample for metallurgical testing. The deposit was discovered in 1903 and has been worked intermittently. It has a production record of about 273,000 tons of ore. The first production of about 150,000 tons was treated in a cyanide plant 2 miles west of Barstow, Calif. The extraction of gold was not satisfactory because of the presence of copper minerals. Since 1910 the ore has been shipped to various smelters in Arizona and California for use as a flux.

Jan 1, 1957

By R. O. Dannenberg

A metallic displacement process, utilizing easily available steel wool or steel window screen, was devised and successfully used for the recovery of silver from waste photographic fixing solutions. Laboratory and prolonged commercial-scale testing established that the iron filament type unit will efficiently precipitate silver, as a high-grade sludge, from acidic waste photographic fixing solutions ranging in grade from less than 1 to over 10 grams of silver per liter. Data and design information are presented to facilitate the construction and operation of a practical unit of any desired size. A smelting process for recovering pure silver from precipitated sludge containing 27 to 80 percent silver was devised.

Jan 1, 1968

By A. J. Barry

An apparatus and procedure have been developed for testing the anchorage effectiveness of slotted-type bolts. The apparatus consists of: (1) A hydrualic Jack assembly for loading the bolt and (2) a device (extensometer or cathetometer) for measuring displacement of the bolt as it is loaded. This apparatus and procedure permit measurment of anchor slip for loads up to the yield load of the bolt. Two representative makes of slotted-type bolts (a total of 94 bolts) were tested in typical sandstone and shale mine roof. Analysis of the test results showed that (1) anchorage capacities up to the yield load of the bolts can be developed in either rock type; (2) the shape of the slotted end of the bolt affects the ease with which the bolt can be driven; (3) all bolts for which the driving distance was more than 1.25 inches produced satisfactory anchorage in both rock types (thus, driving distance can be used as a criterion for satisfactory anchorage); (4) for the group of bolts that was satisfactorily anchored the anchor slip was unaffected by the type of bolt but was considerably larger in shale than in sandstone; and (5) the bolt expansion, that is, the amount the wedge expands the prongs in excess of the diameter of the hole, can also be employed as a criterion for satisfactory anchorage. Although the bolt-expansion and driving-distance results do not differ appreciably, the latter is recommended because it is easier to determine.

Jan 1, 1954

By A. C. Johnson, McHenry Mosier

The Bureau of Mines has adapted its activities to needs of national defense and to conditions brought about by the war program . Its work is now oriented solely to war problems . After studying about 1,600 deposits of war minerals , exploration projects have been undertaken on 96 of the most promising , of which 56 have proved successful . These have indicated that 56 million tons of ore of commercial or near -commercial grade can be utilized to meet war requirements . Included in this amount are 1 million tons of tungsten ore ; 4 million tons of chromite ore, 10 million tons of manganese ore , 2 million tons of antimony ore , 1 million tons of mercury cre , and 28 million tons of iron ore . Work done in connection with exploration projects included 172,000 feet of surface trenching , 210,000 feet of drilling , and 21,000 feet of shaft sinking . Nearly 100,000 samples were taken, on which 500,000 analyses were made . Extensive metallurgical tests were made on ore from many of these deposits , both in the laboratory and in pilot plants , in connection with research to develop metallurgical processes for their treatment .

Jan 1, 1943

By K. J. Liles

The Federal Bureau of Mines conducts a comprehensive test program on clay and shale at the Tuscaloosa Metallurgy Research Center. All samples are subjected to standard preliminary ceramic tests, which include firing formed briquets at temperatures ranging from 1,000° to 1,250° C to identify firing range and colors, and quick-firing to determine bloating characteristics. Materials that shop potential as structural products are further tested after either extrusion or dry-pressing. If the quick-fire test is positive, bulk samples can be fired in a rotary kiln to evaluate their potential as light- weight aggregate A number of miscellaneous tests also can be conducted if requested. These tests determine properties such as refractoriness (pyrometric cone equivalency), oil-bleaching characteristics, oil absorbency, viscosity for drilling-mud applications, sand-bonding properties for foundry usage, and pelletizing characteristics.

Jan 1, 1977

By Robert C. Johnson

Single crystal whiskers of ZrO2 and TiO2 were grown by solution and crystallization of these oxides in molten baths. Mixtures of Na2B407 and LiC1 were the most suitable growth media for zirconia. Sodium borate alone and Na2CO3 plus SiO2 were best suited for titania. The solubilities of zirconia and titania in molten sodium borate were determined, Whether zirconia whiskers were dendritic or nondendritic depended on the temperature used. The best single crystal whiskers were grown below 1,100° C. Titania whiskers always grew as single crystals. The tensile strengths of zirconia and titania whiskers were about 15,000 psi and 50,000 psi, respectively. Modulus of rupture was about 49,000 psi for zirconia whiskers and 75,000 psi for titania whiskers. Chemical analyses showed the zirconia and titania whiskers to be pure. The zirconia and titania whiskers were shown by X-ray analysis to be, respectively, baddeleyite and rutile.

Jan 1, 1965

By E. C. Lane

The motor gasoline that is being marketed in the United States this summer is slightly more volatile than that sold a year ago. The increase in volatility is shown by a lowering of the distillation temperatures, ranging from 2°F. at the average initial boiling point to 4°F. at the average end point. During the past nine years the Bureau of Mines has made semiannual surveys of the gasoline marketed in the United States, the survey just completed being the eighteenth in the series. The cities in which samples were collected have been chosen as representative of the more important marketing territories, as it is obviously impracticable to obtain a sample of every gasoline sold in the entire country. Samples were collected in Omaha as well as in the 11 cities where samples were taken last winter. It was believed advisable to include samples from Omaha in order to give a better balance to the survey for the country as a whole.

Jan 1, 1928

By Robert L. Jones, Clifford Dunham

"INTRODUCTION The Wah Wah mine was examined 3/ by the Bureau of Mines in September, and a project was started in November 1942. Assistance was given by the Federal Geological Survey in formulating proposals and plans, and two geoloists were assigned to map the surface and underground workings in October 1942.HISTORYThe Pine Grove mining district was organized in 1S73, but no work was done there until it was reorganized in 1879, after which it is reported that a little ore was shipped. The Wah Wah Mining Co. was incorporated September 2, 1937. Prior to that time, predecessor organizations had spent approximately $122,000 on the property now held by this company. The board of directors of the Wah Wah Mining Co. approved expenditure of $47,652.14 from September 1937 to June 1942 for development. This work was confined to the Tasso shaft and connecting levels. Shipments in 1939 amounted to 925.789 dry tons with a gross value of $12,477.83. This ore contained 20,130 pounds lead, 1,390 pounds copper, 7,434 ounces silver, and 65.09 ounces gold. The mine was idle from July 1941 to November 1942, when, the Bureau initiated a project to unwater the Tasso shaft and proceed with the exploratory work as outlined in the War Minerals Report."

Apr 1, 1946

By Edward W. Parsons

Conventional rock-bolt anchors often fail when installed in weak formations. The purpose of this work was to develop an anchor that would utilize an explosive charge to secure anchorage in any type of rock. Laboratory work to develop a rock-bolt anchored by explosive forming was initiated using rock-bolt models which had a drilled explosive chamber and were composed of various metals. This was followed by the use of several types of seamless tubing which were expanded with a water-coupled explosive capsule. By attaching a length of solid bolt to the anchor tube, a prototype explosive-anchored rock bolt was made. More than 150 laboratory models were expanded during this phase of development, During two field tests in underground mines (A and B) and one in an open- cut mine (C), 87 explosive-anchored bolts, 9 slot-and-wedge bolts, 2 bolts anchored with expanding grout, and 28 expansion-shell bolts consisting of three types of shells were installed and subjected to pull tests. The field tests were run to determine the effects of variables such as the amount and placement of the explosive charge, design changes in the bolt, and the effect on anchorage of different pull-test techniques. The field tests revealed the following: Mine A. The explosive-anchored rock bolt was feasible, but changes were necessary in bolt materials and in some details of bolt design. Mine B. The design and materials of the bolt gave excellent results in hard fractured rock, but no information was obtained concerning variations in the dimensions of the anchor unit or in the explosive charge. Nine C. Varying the explosive charge to produce a beaded surface on the bolt tube and tightening of the anchored bolt before pull-testing were found to increase significantly the anchorage obtained in soft ground.

Jan 1, 1963

By M. D. Carver

This investigation was undertaken by the Bureau of Nines to determine the effects of impurity levels on the mechanical properties of columbium at low temperatures. High-purity, electron-bombardment-melted columbium was purchased and used as a basis material. Variations in impurity levels were obtained by arc-melting charges containing definite amounts of added impurities. Tensile tests were conducted at low temperatures. Results showed the almost pure basis metal to be ductile at minus 194° C., the lower limit of the range used, Ductility of less pure columbium appeared to depend on interstitial element content. The ductile-to-brittle transition temperature appeared to be raised by increasing carbon content in the range of 50 to 730 parts per million, nitrogen content in the range of 50 to 200 parts per million, or total interstitial element content in the range of 240 to 1,380 parts per million. Some evidence was obtained indicating that decreasing cold work also raised the transition temperature, but recrystallization appeared to have no effect on it. Variations in interstitial element levels appeared to have little or no effect on ultimate strength of columbim in the range of room temperature to minus 194° C, Physical metallurgy studies of massive arc-melted and electron-bombardment- melted columbium were included in the columbium-tantalum research work assigned to the Albany Metallurgy Research Center in fiscal year 1959.

Jan 1, 1961