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By P. N. Anyalebechi

A comparative study of the mechanical properties of automotive steering knuckles produced by three different shape-casting related processes has been conducted. It involved the characterization of the tensile and fatigue properties of aluminum alloy A356 knuckles produced by the vacuum/pressure riserless casting (VRC/PRC), pressure counter pressure casting (PCPC), and the hybrid Cobapress (a casting-forging) processes, in accordance with the appropriate ASTM standards. Surprisingly, the knuckles produced by the hybrid Cobapress process exhibited the lowest strength. For example, the average 0.2% yield strength of the Cobapress knuckles was 31 MPa and 40 MPa less than that of the VRC/PRC and PCPC knuckles, respectively. However, between stresses of 150-200 MPa, the fatigue lives of the VRC/PRC, PCPC, and Cobapress knuckles were comparable. But above 200 MPa, the Cobapress knuckles exhibited the lowest fatigue life. The observed differences in the mechanical properties are attributed to the inherently different microstructures of the different knuckles.

Jan 1, 2009

By Bradford F. Townsend, Marc R. Kritzer, Michael F. Roach, Dennis Ofiara

All Rights Reserved. Printed in the United States of America. Information contained in this work has been obtained by SME, Inc. from sources believed to be reliable. However, neither SME nor its authors guarantee the accuracy or completeness of any information published herein, and neither SME nor its authors shall be responsible for any errors, omissions, or damages arising out of use of this information. This work is published with the understanding that SME and its authors are supplying information but are not attempting to render engineering or other professional services. If such services are required, the assistance of an appropriate professional should be sought. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher. Any statement or views presented here are those of the authors and are not necessarily those of SME. The mention of trade names for commercial products does not imply the approval or endorsement of SME.

Dec 1, 2008

By John G. Parker

The rare-earth elements, sometimes known as the lanthanides, comprise the series of 15 chemically similar elements with atomic numbers 57 through 71. Yttrium, with atomic number 39, is often included in the group, because its properties are similar and it more often than not occurs in association with the lanthanides. Thorium is included in this survey due to its close association with the lanthanides, particularly in the mineral monazite. The lanthanides were first recognized as elements around 1750 and were the subject of much study by chemists during the 19th century. The purely chemical methods then available failed to resolve the strange intimate relationships between these elements, and it was not until about 1920 that the full series was explained.

Jan 1, 1971

By R. E. Collom

The commercial development of petroleum and natural gas fields has reached its present status within 60 years and is still considered by some operators to be "100 per cent wildcatting." 1 A tendency to drill for gusher production, the production that yields big returns in spite of any mechanical defects in drilling methods, has frequently caused drillers to pass by oil-bearing strata of comparatively small yield and actually to overlook rich oil zones in proved fields; in addition, whole fields have been ruined by water because development methods were never carried beyond a hole-in-the-ground stage.2 Unfortunately, the petroleum industry has no mine dumps or tail. ing piles as at metal mines to yield fortunes through later and bette!' methods of treatment. The wasted oil and gas are gone, as are the time, money, and effort wasted in ill-advised or haphazard drilling. Probably as production costs increase less oil will be wasted, but the need to develop and produce from sands of low yield will become more urgent with the increase in consumption of oil and the decrease in supply. Hundreds of wells are producing steadily as the result of months and perhaps years of careful prospecting and of tests during drilling. The Bureau of Mines has studied the testing and drilling methods used at such wells, and presents in this paper a criticism of these methods and suggestions on future work. The term pr08- pecting here means correct identification and measurement of strata as they are exposed by the drill. The term testing means the determination of the kind and amount of fluid stored within the pores or crevices of any stratum exposed in the hole.

Jan 1, 1922

1. Domestic Production and Use: In 1977, 12 companies operated 31 primary aluminum reduction plants, with 3 firms accounting for 65% of production capacity. Washington, Oregon, and Montana accounted for 31% of the total capacity; Gulf Coast States 23%, Northern States 26%, and other Southern States 20%. Based on estimated producer prices output of primary metal in 1977 Has valued at $4.6 billion. Aluminum consumption by 25,000 firms was centered 'in the East Central United States. Of aluminum consuming industries in 1977, building accounted for about 25%; packaging 22%; transportation 21%; electrical 11%; consumer durables 9%; and other uses, 12%.

Jan 1, 1978

Jan 1, 1994

Mercury has been used by mankind since prehistoric times. It has been, and is now, widely used in industry and medicine and has unique properties which make direct substitution difficult or impossible. At present its principal uses are for electrical apparatus, control instruments, electrolytic soda preparation, mildew-proofing paints, pesticides, and medical and dental preparations. Deposits of mercury are less common than those of other base and precious metals, but some of the deposits are very large and have been ample to meet the world's past demands. The price of mercury has had many sharp fluctuations, but in general, the limited number of producers has resulted in a more stable price structure than that of many other commodities. The United States has been one of the main producers of mercury, and from 1850 to 1961 produced 3,247,704 flasks. Yearly production since World War I1 has varied from 4,535 to 38,067 flasks. An estimate of domestic resources of mercury producible at various price ranges was prepared for each mercury mine by combining specific knowledge of mercury mineralization with estimates of potential, based on geologic information and past production history. The sum of the individual estimates for each price range is shown in a table. A parallel estimate of nationwide production potential was made from a study of past price and production relationships. These were analyzed by plotting yearly production figures against the previous year's price, expressed in dollars of constant purchasing power. An equation was fitted to the data by mathematical means and was used to extend the curve into areas of higher than historic prices. Potential production rates at various price levels were taken from this graph. The estimated yearly production rates were used to make an estimate of total potential based on the premise that production rates and reserves have a proportionate relationship. The rate of developing mercury reserves during the period from January 1944 to January 1962 is considered, and it is shown that if this rate can be continued, the mercury resources of the United States, at a constant dollar price of $500 per flask, are adequate to support a production of 60,000 flasks per year for 30 or more years. This publication contains a history and description of the mercury industry in every State which has had production and individual descriptions of all mercury properties which have reported significant production. Accompanying tables give the important facts about all known mercury occurrences.

Jan 1, 1965

Mercury has been used by mankind since prehistoric times. It has been, and is now, widely used in industry and medicine and has unique properties which make direct substitution difficult or impossible. At present its principal uses are for electrical apparatus, control instruments, electrolytic soda preparation, mildew-proofing paints, pesticides, and medical and dental preparations. Deposits of mercury are less common than those of other base and precious metals, but some of the deposits are very large and have been ample to meet the world's past demands. The price of mercury has had many sharp fluctuations, but in general, the limited number of producers has resulted in a more stable price structure than that of many other commodities. The United States has been one of the main producers of mercury, and from 1850 to 1961 produced 3,247,704 flasks. Yearly production since World War II has varied from 4,535 to 38,067 flasks. An estimate of domestic resources of mercury producible at various price ranges was prepared for each mercury mine by combining specific knowledge of mercury mineralization with estimates of potential, based on geologic information and past production history. The sum of the individual estimates for each price range is shown in a table. A parallel estimate of nationwide production potential was made from a study of past price and production relationships. These were analyzed by plotting yearly production figures against the previous year's price, expressed in dollars of constant purchasing power. An equation was fitted to the data by mathematical means and was used to extend the curve into areas of higher than historic prices. Potential production rates at various price levels were taken from this graph. The estimated yearly production rates were used to make an estimate of total potential based on the premise that production rates and reserves have a proportionate relationship. The rate of developing mercury reserves during the period from January 1944 to January 1962 is considered, and it is shown that if this rate can be continued, the mercury resources of the United States, at a constant dollar price of $500 per flask, are adequate to support a production of 60,000 flasks per year for 30 or more years. This publication contains a history and description of the mercury industry in every State which has had production and individual descriptions of all mercury properties which have reported significant production. Accompanying tables give the important facts about all known mercury occurrences.

Jan 1, 1965

Norton Co., a manufacturer of abrasive products and diamond drilling and coring bits for oil and gas exploration, is building a $19.1 million addition, scheduled for completion in late 1980, to the Huntsville, AL. The plant makes alumina-zirconia abrasive grains used in grinding wheels and coated abrasives. ALUMINUM Martin Marietta Aluminum Inc. announced plans to expand production capacity of its 112,000-ton-per-year primary aluminum smelter at Goldendale, WA to 177,000 tons per year. The $125 million expansion was scheduled to come onstream in 1981. The Aluminum Company of America announced plans to restart a fourth potline during October at its 185,000-ton-per-year Point Comfort, TX primary aluminum smelter.

Jan 1, 1979

By Hazel J. Stratton

IN THE HALF-CENTURY that has passed since the Bureau of Mines was established in July 1910, the research and technologic investigations conducted by the Bureau's scientists, engineers, and other personnel have helped significantly in improving health and safety in the mineral industries and have contributed substantially in conserving the Nation's mineral resources through improved techniques in the mining, treatment, and use of mineral commodities. From Bureau laboratories have come new materials for industry and better methods of extracting and processing minerals and mineral fuels. Bureau safety investigations-complemented by equipment testing and by programs of mine inspection and education-have brought about safer and more healthful working conditions.

Jan 1, 1960

The Bureau of Mines, through its Minerals Availability Program (MAP), investigates the mineral supply potential of the United States and market economy countries (MEC's) for a number of minerals considered essential to the U.S. industrial base. Major activities include identification of important mines and mineral deposits, estimation of their mineral resources and production costs, and availability and sensitivity analyses. Products include data print-outs of geological and engineering information, discounted- cash-flow rate of return (DCFROR) analyses of individual mining operations, commodity availability appraisals, and analytic services to Government agencies. These products are used in assessing the mineral supply position of the United States: in setting priorities for research aimed at reducing production costs and minimizing adverse environ- mental impacts and regulatory compliance costs of mining and mineral processing operations; and in formulating and evaluating Government policies that affect minerals. Bureau MAP data and analyses have been provided to the executive and legislative branches to aid in consideration of trade, tax, and stockpile policy issues. A study of the economic potential of selected seabed mineral resources supports the regulatory responsibilities of the Department of the Interior in the U.S. Exclusive Economic Zone. Analytic studies of mineral project viability, industry competitiveness, and import dependencies were also undertaken for, or in cooperation with, U.S. and foreign government agencies, industry and trade organizations, and international lending institutions.

Jan 1, 1987

By C. A. Geffen-Fowler

This report, sponsored by the Bureau of Mines, presents the results of an examination of the safety of the Blind Shaft Borer (BSB) shaft sinking system and an alternative modified BSB design concept in comparison to conventional shaft sinking technology. Detailed study of the two systems was also performed to identify and recommend design changes for optimum safety conditions. A comparison of the BSB systems with conventional shaft sinking was made on the basis of relative risk levels. Risk incorporates both the frequency and the potential consequence of accidents. A safety evaluation of the component operations of the two BSB systems was performed using a Failure Modes and Effects Analysis (FMEA) methodology. The results of this analysis show generally that both BSB systems are safer than conventional shaft sinking. The potential risk of conventional shaft Sinking operations could be reduced by over 30%, on the average with the use of the original BSB system, and by an average of about 10% with the modified BSB. Design change recommendations to further improve the safety of these systems include a better fire suppression system, improved man haulage systems and more compact hydraulics. An operational safety manual was also developed for the modified BSB system.

Jan 1, 1981

By Keith L. Harris

The U.S. economy continued to grow moderately in the third quarter, but at a slightly higher rate than in the previous quarter. According to the Department of Commerce's preliminary estimate, real gross national product (GNP) grew at a seasonally adjusted annual rate of 3.3% during the third quarter of 1985, compared with a revised 1.9% for the second quarter and 1.6% for the third quarter of 1984 (table 1). Civilian unemployment dropped from the constant 7.3% rate between February and July to 7.0% in August and 7.1% in September. Employment on nonagricultural payrolls continued to increase (table 2), resulting in a continued rise in personal income, which in turn supported growing consumer purchases. Although purchases of services continued to provide the underlying foundation for the economic growth, the manufacturing sector received additional stimulus from significant increases in consumer purchases of durable goods, particularly automobiles. The increased demand for durable goods resulted in significantly higher industrial production for August and September, compared with levels attained previously this year (table 3). Capacity utilization increased to 80.5% in August but returned to 80.2% in September, matching the 1985 low previously reached in July (table 4). The real net export deficit grew only $0.2 billion in the third quarter; at $34.0 billion, however, it continued to exert a negative influence on the economy. On September 22, in an effort to reduce the deficit and make U.S. goods more competitive on world markets, the U.S. Government agreed to cooperate with the Governments of France, the Federal Republic of Germany, Japan, and the United Kingdom in attempting to lower the-value of the dollar in relation to other world currencies. Low inventories, rising factory orders and construction spending, the possibility of a lower U.S. dollar, and aggressive automobile production plans announced by domestic producers for the fourth quarter indicate the potential for an increase in manufacturing activity in the United States.

Jan 1, 1985

Martin Marietta Aluminum, Inc. followed Howmet Aluminum Corp., Revere Copper and Brass, Inc. and Anaconda Co. in lifting August prices of 99.5 percent unalloyed aluminum ingot by 3 cents to 56 cents per pound. Prior to these moves, Kaiser Aluminum and Chemical Corp. raised its June ingot listings by 4 cents to 57 cents and Consolidated Aluminum Corp., 4.5 cents to 57.5 cents. Domestic merchants increased July quotes by slightly more than 1 cent to 51.3-51.8 cents per pound. ARSENIC The Occupational Safety and Health Administration (OSHA) issued new standards, effective August 1, for worker exposure to inorganic arsenic, a toxic substance linked by OSHA to lung and lymphatic cancer. The new standard will limit worker exposure to 10 micrograms per cubic meter of air over an 8-hour period, a drastic reduction from the previous standard of 500 micrograms for a like period. Implementation of the new standards may be the most difficult and costly for copper smelters where arsenic is associated with the copper feed material but problems will also be encountered by producers of arsenic containing products such as for pesticides and herbicides. The new standards allow use of personal protective gear for workers as an interim measure until plant engineering controls can be put into effect.

Jan 1, 1978

Jan 1, 1900

By G. Van Weert

In the spring of 2010 double refractory ores from historical stockpiles were processed through Barrick's Goldstrike pressure oxidation facility, thereby providing preg robbing feeds for a variety of metallurgical testwork. This paper describes the effects of amount, type, place and time of addition of activated carbons on CIL gold recovery and shows that native carbon in plant PDX'ed discharge solids can still preg rob gold loaded activated carbon.

Jan 1, 2011

By Robert C. Weisner

Current production costs and market conditions in the potash industry of the Carlsbad area were studied to determine the potential values of the potash mineral resource that would be lost or foregone if the Waste Isolation Pilot Plant (WIPP) facility is constructed on the proposed site in that area. The purpose of the WIPP project is to investigate the possibility of developing a nuclear waste disposal plant in the salt formations at the site. Analyses were made of all potash deposits determined to be in the site. Mining and processing under the most favorable recovery systems were considered. Value determinations were based upon estimated operating and capital costs of current mine-mill operations in the Carlsbad area. This study was made for the Energy Research and Development Administration (ERDA) by members of the Federal Bureau of Mines Minerals Availability System staff.

Jan 1, 1979

By F. H. Samuel, H. Tahiri, S. Valtierra, H. W. Doty, A. M. Samuel

L'affinage des grains dans les alliages d'aluminium consiste à augmenter le nombre de sites de cristallisation de la phase a-Al afin d'obtenir une structure fine. Les alliages mères de type Al-Ti-B sont largement utilisés comme raffineurs des grains. Cette étude a pour but d'établir des mécanismes convenables d'affinage des grains dans l'alliage A356 en utilisant cinq alliages mères et deux températures de coulée (750°C et 950°C). Les résultats montrent que la phase a-Al prend une forme selon l'alliage mère ajoute; les échantillons coules a haute température montrent une taille de grain plus grosse; les températures de germination et de croissance augmentent avec I' augmentation du Ti ou du B et la taille des grains diminue. L'alliage mère Al-4%B montre une puissance remarquable en comparaison d'autres alliages mères. Pour cet alliage mère, le titane résiduel dans l'alliage A356 réagit avec le bore pour former TiB2 qui, par la suite, agit comme un germe actif pour la phase a-Al.

Jan 1, 2006

By Paul M. Tyler, R. M. Santmyers

Platinum and its allied metals osmium, iridium, rhodium , palladium, and ruthenium are the most costly of the better-known metals and combine properties that make them unique among the elements . For a number of isolated uses substitutes have been found which are cheaper and quite as satisfactory ; but none will replace platinum in many of its varied uses , and there is a large and growing demand for purposes for which no economical substitutes are known . As this paper is being written the supply of platinum tends further to increase as a result of the exploitation of newly developed resources and the expansion of production from older sources . In obedience to economic law prices have declined steadily . Buyers , always reluctant to commit themselves on a falling market , have maintained a waiting attitude , and consumption trends are not clearly indicated . Should platinum again approach the price of gold , the natural tendency would be to use more of the metal . In recent years , however , the industrial and scientific uses of platinum have become subordinate to its consumption in jewelry . In matters of personal adornment the popular whim and not practical utility is the dominant factor in demand , and it does not follow that lowered prices will stimulate demand . The substitution of white gold and certain plated goods for platinum may be checked by cheaper platinum , but a fickle public that turned from gold to platinum when platinum became the more costly metal can not with certainty be expected to buy more platinum jewelry because more of the metal than formerly may now be had for the same price . The dearth of platinum during and for some years after the World War had a profound effect upon prices , and this in turn wrought important changes in the field of consumption . When prices advanced the chemical industry, formerly the leading consumer of platinum, was forced to economize in its consumption of the metal and to substitute other metals whenever it could . Somewhat similar conditions resulted in the electrical industry and in the use of platinum in dentistry . Some of these former outlets are permanently closed , and others may be reopened now that platinum prices have receded to pre-war levels , but despite the general expansion of industrial and scientific activity since 1913 the demand for platinum outside the jewelry trade has suffered a net decline . Since the metallurgy of platinum is relatively simple the reason for its high price is its relative scarcity in the earth's crust . An interesting speculation set forth by certain geologists attributes the extraordinarily high density of the interior of the earth in part to the presence of iron alloyed with substantial amounts of platinum and other related metals . In support of this hypothesis it may be said that platinum is often found in meteorites , and known deposits in the earth's crust are all of deep - seated origin . However , even if there were a high concentration of platinum in the interior of the earth it would be next to impossible at the present state of our knowledge to make it available , and the world would continue to depend for its supply on deposits found within minable depths below the surface . For many years before 1914 the world obtained its supply of platinum metals primarily from Russia , which before the war produced as much as 300,000 troy ounces in a year , or approximately 95 per cent of the world output . Despite fluctuations due to internal political disturbances Colombia managed to account for 3 to 4 per cent , leaving the rest of the world to furnish the remaining 1 to 2 per cent .

Feb 1, 1931

Many of the difficulties faced by the U.S. mineral industry in 1982 and 1983 emanated from the worldwide recession, from the high value of the U.S. exchange rate, and, in part, from actions taken by foreign governments to protect selected industries. While some problems will be minimized with continued worldwide economic recovery, others remain and may require special attention by U.S. policymakers. These problems include declining U.S. production capacity in selected mining and mineral processing industries, the impact of the high value of the U.S. exchange rate, and protectionist trade practices by competitor nations. Illustrative of the last is the International Trade Commission (ITC) determination in June 1984 that both the domestic steel and copper industries have been substantially injured by foreign imports. In its July 1984 recommendations to the President, the ITC suggested higher tariffs and quotas for 5 years on 70 percent of steel imports but conditioned the aid on cost-cutting and modernization steps by the domestic industry. In the copper decision, two commissioners recommended increased duties, two recommended that quotas be imposed, and one recommended that no relief be provided. The President decided in September to seek voluntary restraint agreements with nations that export steel to the United States and rejected both quotas and higher tariffs on copper imports. General Economic Setting This decade opened with the U.S. mineral industries struggling to deal with double-digit inflation, record high peacetime interest rates, and almost 7 years of oil-cartel-induced energy price increases that seriously affected the profitability of energy-intensive industries such as mineral production and processing.

Jan 1, 1985