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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 D. A. J. Swinkels

The problem of determining oxygen levels in liquid steel to aid in deoxidation control has received general attention for a number of years. Work in this direction started at the B.H.P. Central Research Laboratories early in 1967 with an evaluation of sampling techniques followed by vacuum fusion analysis to determine the oxygen content of the samples (1). It was found that these techniques had a number of drawbacks if they were to be used for deoxidation control. The method of analysis was rather too slow to allow effective control and measured total oxygen level rather than dissolved oxygen. Furthermore, the results were found to be very variable due to slag entrainment in the samples. Attention therefore turned to the galvanic cell method using a solid oxygen ion conductive electrolyte such as cubic stabilised zirconia. The ionic conductivity properties of electrolytes such as (ZrO2) 85 (CaO).15 had been studied by a number of investigators and had already been applied to the measurement of oxygen activity in gases, in lower melting metals such as copper, lead, tin, silver, alkali metals and indeed the first studies in steel had been made (2,3). Since then the results of a number of studies in the development of an expendable oxygen probe for steel have been reported (4-9).

Jan 1, 1972

THE sessions of the Institute were opened on Tuesday evening, October 26th, at Garrett's Hall, by Mr. Charles A. Otis, Chairman of the Local Committee of Arrangements, who welcomed the Institute to Cleveland, and introduced Col. Charles Whittlesey, who ad¬dressed the Institute briefly on the coal deposits of Ohio. Col. Whittlesey described the situation and character of the coal-beds of the State, and gave a short history of the use of raw coal in the manufacture of pig-iron, and spoke of the excellent quality of metal produced. The aid that a body of scientific miners and metal¬lurgists were capable of giving in the development of coal and other mineral resources was dwelt upon, and the hope expressed that the visit of the Institute to Cleveland might be profitable as, well to its members as to the citizens of the State. The President, Mr. A. L. Holley, responded to the welcome of Mr. Otis and of Col. Whittlesey, and read an introductory address on Some Pressing Needs in the Iron and Steel Manufacture. The following members and associates, duly proposed and indorsed by the Council, were then elected MEMBERS. Alfred S. Bertolet, - Youngstown, Ohio. Henry Binnse, - Chicago, Ill. John Birkinbine, - Philadelphia. Andrew A. Blair, - Watertown Arsenal, Mass. Ogden Bolton, - Canton, Ohio. Lloyd Booth, - Youngstown, Ohio. E. Borda, - Philadelphia. N. P. Bowler, - Cleveland, Ohio. Alexander E. Brown, - Cleveland, Ohio. C. F. Brush, - Cleveland, Ohio. S. M. Carpenter, - Cleveland, Ohio. James Cartwright, - Youngstown, Ohio. Henry Chisbolm, - Cleveland, Ohio. Wilson B. Chisbolm, - Newburgh, Ohio. W. H. Clarke, - Millertown, Pa. James E. Clayton, - Ore Knob, N. C.

Jan 1, 1876

The sessions of the Institute were opened on Tuesday evening, October 26th, at Garrett's Hall, by Mr. Charles A. Otis, Chairman of the Local Committee of Arrangements, who welcomed the Institute to Cleveland, and introduced Col. Charles Whittlesey, who addressed the Institute briefly on the coal deposits of Ohio. Col. Whittlesey described the situation and character of the coalbeds of the State, and gave a short history of the use of raw coal in the manufacture of pig-iron, and spoke of the excellent quality of metal produced. The aid that a body of scientific miners and metallurgists were capable of giving in the development of coal and other mineral resources was dwelt upon, and the hope expressed that the visit of the Institute to Cleveland might be profitable as well to its members as to the citizens of the State. The President, Mr. A. L. Holley, responded to the welcome of Mr. Otis and of Col. Whittlesey, and read an introductory address on Some Pressing Needs in the Iron and Steel Manufacture. The following members and associates, duly proposed and indorsed by the Council, were then elected MEMBERS. Alfred S. Bertolet,.. .. . Youngstown, Ohio. Henry Binnse,. Chicago, Ill. John Birkinbine,.. .. . Philadelphia. Andrew A. Blair,. .. .. Watertown Arsenal, Mass. Ogden Bolton,. .. .. Canton, Ohio. Lloyd Booth,..Youngstown, Ohio. E. Borda,..Philadelphia. N. P. Bowler,.. .. . Cleveland, Ohio. Alexander E. Brown,.... Cleveland, Ohio. C. F. Brush,.. .. .Cleveland, Ohio. S. M. Carpenter,.. .. . Cleveland, Ohio. James Cartwright,.. .. . Youngstown, Ohio. Henry Chisholm,.. .. . Cleveland, Ohio. Wilson B. Chisholm,.. .. . Newburgh, Ohio. W. H. Clarke,.. .. . Millertown, Pa. James E. Clayton,. .. .. Ore Knob, N..C.

By D. P. Harris

This paper surveys a few of the quantitative exploration models that might be of interest to an ex-plorationist seeking to apply methods of operations research to mineral exploration. A general development of each model is presented, and the model is evaluated relative to the exploration activity. Finally, a philosophy of exploration and mineral resources is presented, and a possible exploration strategy incorporating concepts of some of these models consistent with this philosophy is proposed. The high cost of conducting an effective exploration program has generated an increasing interest in methods of optimizing the allocation of the resources of a firm engaged in mineral exploration. As a step towards this, mathematical models have been formulated which are designed to quantify those variables of mineral exploration in such a manner that they can be integrated with all phases of the firm's operations so as to optimize its profit objective. QUANTITATIVE MODELS General: Exploration models express at least two concepts: mineral occurrence and effectiveness of search. In simplest terms, an exploration model might be formulated mathematically as follows: P(X) = F(X) . G(X), where P(X) = the unconditional probability of discovery of X deposits, F(X) = the probability of occurrence of X deposits, and G(X) = the probability of discovery of X deposits, conditional upon their existence in the search area. With these general models as a basis of reference, some of the specific exploration models are examined below. The Allais Model: DEVELOPMENT - M. Allaisl performed the first study in which a philosophy of exploration was formulated into a probability framework. His objective was to estimate the economic profitability of the exploration of the Algerian Sahara. Allais divided the Algerian Sahara into blocks of land (called cells) 10 km square and defined the random variable, X, as the number of mining districts per cell. Thus, F(X) would describe the probability of 1, 2, or n mining districts occurring within any cell of the search area. Allais reasoned that his best information as to the form of the distribution, F(X), was the number of mining districts per cell that had been found in well explored areas in the world, such as the Western States of the U.S. He found that the Poisson function produced a reasonably good fit to the distribution of districts in these explored areas: where? is a parameter, such as the average number of districts per cell. Thus, by determining the value

Jan 1, 1968

By C. E. Webber

THE economical recovery of the valuable constituents from the effluent of gas-con-densate wells has developed into a problem of balancing the cost of recovery against the cost of compressing the residual gas back into the formation. A possible method of extracting the gasoline and distillate from the natural gas is by oil absorption at high pressures. In order to design and evaluate an absorption plant, fundamental data on the composition of the coexisting hydro-carbon vapor and liquid phases at various temperatures and pressures are essential. A review of the literature indicated that the necessary data for the design of such plants are lacking. The nearest approach to desired published data is that of Katz and Hackmuth,5 who experimentally deter-mined the composition of the coexisting vapor and liquid phases in a natural gas-crude oil system at pressures up to 3000 lb. per sq. in. and at temperatures from 40° to 200°F. This paper presents the results of the experimental determination of the equilib-rium distribution of the hydrocarbons methane through hexane between natural gas and a typical absorber oil. The ranges of temperature and pressure chosen were from 33° to 180°F. and from 100 to 5000 lb. per sq. inch.

Jan 1, 1940

By Robert R. French

Beneficiation of low-grade nonmetalliferous mineral deposits by electronic color sorting is currently undergoing a period of rapid development. For those deposits in which the specific gravity, strength, soundness, and electric and magnetic properties of the ore and gangue are similar, the possibility of separation by color, reflectivity, or fluorescence offers hope for the utilization of much poorer quality ore than previously thought possible. For those ores in which consistency of color is required or for which a dry process is preferred, the electronic color sorter is particularly adaptable. Tests performed late in 1966 and reported herein are the result of the continued interest in the dry beneficiation of gypsum and the development of higher capacity color sorting machines. The ore used was a discarded fraction that consisted of – 1 ¼ -in, to + 3/8 -in. ore containing 63.1 to 71.4% (average 67.7%) gypsum. This material was contaminated by various amounts of both carbonate rock and shale, but no pretreatment was performed other than screening to closer size limits before electronic color sorting.

Jan 4, 1969

By V. V. Ivanov, A. I. Khanchuk, E. V. Mikhailik, M. G. Blokhin, P. E. Mikhailik

At present, marine ferromanganese crusts of seamounts are of great interest as a source of high-tech metals. The metals most enriched in these deposits are essential for a wide variety of green-tech, emerging-tech, and energy applications (Hein et al., 2013). There is a grate number data on the content of major and minor metals (thousands analyses). However, information on the content of such elements as platinum, gold and silver in the world literature is limited. The concentrations (N – number of analyses) of platinum, gold and silver in the Pacific are 418 ppb (N = 105), 35 ppb (N = 72), 1.02 ppm (N = 26), respectively, and in the North Pacific Prime Zone - 477 ppb (N = 66), 55 ppb (N = 13), 0.1 ppm (N = 4); in the Atlantic Ocean is 567 ppb (N = 2), 6 ppb (N = 2), 0.20 ppm (N = 18), in the Indian Ocean, 211 ppb (N = 6), 21 ppb (N = 2), 0.37 ppm (N = 9) respectively; (Hein et al., 2013). The northern part of the Pacific is poorly studied in this question. The samples of ferromanganese deposits (FMD) was recovered from the Govorov Guyot (Magellan seamounts), MZh-33 Guyot (Marshall Islands), as well as the Detroit Guyot (Imperor Ridge) and Yomei Guyot (Fe-Mn placer Holes 431 and 431A DSDP, Imperor Ridge).

Jan 1, 2018

By Isadora Pereira Nunes

O objetivo deste trabalho é estudar o efeito do recobrimento de níquel-nióbio por eletrodeposição na resistência à fadiga de um aço carbono SAE 1020. Os corpos de prova para os ensaios de fadiga foram extraídos de barras de diâmetro igual a 7,94 mm (5/16’’). Os ensaios de fadiga foram realizados por flexão rotativa com carregamento em balanço. Foi empregada uma velocidade de rotação de aproximadamente 1500rpm. Foram realizados ensaios de dureza do aço e da camada depositada de Ni-Nb. Análises microestruturais do aço e das fraturas de fadiga foram realizadas através de microscopia eletrônica de varredura (MEV). Os ensaios de fadiga foram realizados de forma a se obter curvas S-N (curvas de Whöler). Foram realizados três ensaios para cada carregamento. Foi observado que o recobrimento de Ni-Nb proporcionou tendência ao aumento do limite de resistência à fadiga do aço.

Aug 17, 2017

By Dwight L. Sawyer, Roy T. Sorensen

The Bureau of Mines has investigated the recovery of alumina by hydrochloric acid leaching of calcined kaolinitic clay . Bench- scale studies indicated that horizontal belt filtration was a pprraaccttiiccaall method for separating the siliceous residue from aluminum chloride liquor generated in the leaching step . Miniplant -scale continuous testing was performed to evaluate the filter circuits and to compare filtration response of different calcined kaolin feed materials and of different agitatorbaffle designs in the leaching reactors . Soluble alumina recovery with a single filter ranged from 94 pct with minus 10 -mesh feed more than 96 pct with minus 35-mesh or misted feed . Process advantages were confirmed for the calcined misted kaolin feed material prepared by a Bureau-developed misting process . With two filters in series , an overall filtration rate of 100 lb solids /hr.ft - 2 of filter area was attained with a soluble alumina recovery of more than 99 pct . More than 99.5 pct alumina recovery was obtained with a thickener and a two - filter circuit for either the minus 35-mesh or the misted feed . Modifications in leaching reactor design made to decrease particle- toparticle attrition were successful and significantly increased filtration rates and decreased flocculant requirements .

Jan 1, 1965

By Thomas D. Kaufmann

Introduction Mining has always been sensitive to the fluctuating income of downstream customer industries. The industry is now becoming more vulnerable to booms and busts as economic pulsations increase and demand for mining products shows little or no long-term growth. As the general economy has become more cyclical in the last decade, the capital-intensive primary industries have become more aware that timing as well as preparation of survival plans are vital in investment decisions. Strangely, however, some of us have not yet included the business cycle in our feasibility studies. Cyclic prices and volumes and fluctuations in profits and cash flows do not fit our linear models. The increased cyclical nature of our economy is recent and poorly understood. Forecasting peaks and troughs is still more an art than a science. Nevertheless, avoiding business cycle parameters can lead to error in value estimation and contingency planning of new projects. Metal and Mineral Industries More than half the iron and steel, aluminum, copper, lead, zinc, manganese, tin, nickel, molybdenum, cobalt, and chrome that we mine, smelt, upgrade, and recycle goes to construction, transportation, capital goods, and consumer durable industries. All are cyclical. Their products are consumed slowly, so replacement can be postponed in recessions. Purchases of such goods are usually financed by debt, and their customers are sensitive to highly cyclical changes in interest rates. During prosperous periods, people tend to buy capital goods despite high interest rates. Upstream industries also tend to be whipsawed by inventory cycles. With high interest rates and good transportation, downstream fabricators can lighten their inventories during recessions. They know that upstream suppliers can deliver supplies and raw materials immediately, And, with the advent of electronic accounting, the fabricator with timely inventory information can afford to hold fewer contingency stocks. Likewise, when recovery returns, inventories surge back through industry pipelines, accelerating demands on primary supplies. The price elasticity of most primary products is low. Their share of the value of finished products of the industries they supply is generally small. The 60 kg (130 lb) of aluminum in a car is vital. But whether it costs $80 or $130 will not visibly influence the demand for an automobile. With low elasticities of demand, the primary producer is hit with decreases (or increases) in prices and in sales volume, during recessions as well as recoveries.

Jan 6, 1984

By E. H. Griswold

The many complexities arising from our present oil pool proration systems emphasize the need for a suitable standard of property rights. Attempts at conservation and unitization agreements have frequently failed because of the lack of such a standard. The necessity of reducing production to consumption has caused umpires, committees, commissions and other governing bodies to allocate the production of flush fields among the respective owners. The methods of allocation vary widely and conservation of underground reserves is frequently neglected or misused. Critical economic conditions increase, rather than modify, competitive methods. In some fields we have irregular and uneconomically close well spacing. Many operators drill unreasonably large holes, take excessive sand penetrations or leave their wells untubed in order to secure higher potential open-flow tests than their offsets. All of these practices result in economic waste and frequently damage to the pool. Regardless of our agreement with the fundamental principles of proration or unitization, both are actual necessities in many of our present economic situations, and we are in urgent need of a suitable standard of rights to facilitate and simplify their operation. The problems pertinent to unit management are simple and of daily use in many partnership enterprises, but the problems of fair and proper division of production under either proration or unitization are, as yet, subject to controversy. The rights of respective owners must be ascertained and standardized before we can eliminate wasteful practices and still preserve constructive competition in our industry. Valuation of Tracts In a recent unitization conference it was found that each participant had a different basis for calculating the relative values of tracts. Some of these assumptions were as follows: 1. Unrestricted open-flow operation to abandonment. 2. Current proration system to abandonment.

Jan 1, 1933

By Ronald S. Conti

The Bureau of Mines conducted a comprehensive laboratory study of the thermal ignitability of various carbonaceous dust clouds with particular emphasis on various ranks of coal dust. The tests were conducted using a new 1.2-L furnace. Autoignition temperatures of dust clouds were obtained as a function of coal volatility and particle size. Dust particles and gas samples were collected by a rapid-sampling system in order to study the reactions involved in preignition and postignition processes. The autoignition temperatures measured in the new 1.2-L furnace were significantly lower and therefore more conservative than those measured previously in the Godbert-Greenwald furnace. The combined effects of thermal and electrical ignition of dust clouds were also studied in the 1.2-L furnace using electrical discharges of varying energies at ambient and elevated temperatures. The minimum spark energy necessary to ignite a dust cloud decreased significantly as the temperature of the dust cloud increased.

Jan 1, 1983

By AIME AIME

AS a new departure the annual business meeting was held at 4 p. m. on Tuesday, Feb. 16, instead of in the morning, as previously. The retiring President, Robert E. Tally, called the meeting to order and briefly spoke of the large measure of success that had been attained in balancing the budget of the Institute in 1931, so that, although receipts had declined over $26,000 compared to the previous year, expenditures had come within $3,000 of income. He referred in complimentary ,terms to the work of the committees on Membership, Admissions, Papers and Publications, and MINING AND METALLURGY, from which more would be heard late:. He also announced that a large and important committee on economics has been under consideration, and will be announced later. As an evidence of growth it was noted that a new Division, Mineral Industry Education, had been organized just an hour previously.

Jan 1, 1932

By Robert L. Russell, Henry W. Zimmerman

The Bunker Hill mine in the Coeur d'Alene mining district at Kellogg, Idaho, has been a major producer of Pb-Ag-Zn ores since its discovery in 1887. The mine has produced over 29 million tons of ore from some 20 to 25 veins and ore zones and now covers an area approximately 1 mi long by 0.5 mi wide. The active section of the mine extends from 2500 ft above sea level to 1600 ft below sea level. Ore production is presently at the rate of about 1700 tpd. A 2-mi adit, the Kellogg tunnel, at the 2500 elevation provides access to the main shaft area. Ore is hoisted to the adit level through a 5000-ft. 50º-inclined shaft extending to the lowermost haulage level 1200 ft below sea level. Primary shaft service for men and materials is supplied by three major internal inclined shafts equipped with double-drum hoists. Present production requires ten levels to serve for main line track haulage. These range up to 5000 ft in length and are either 200 or 400 vertical ft apart. Also, many intermediate levels exist throughout the mine.

Jan 1, 1971

By Xingye Guo, Yeon-Gil Jung, James Knapp, Zhe Lu, Jing Zhang, Li Li

La2Zr2O7 is a promising thermal barrier coating material due to its low thermal conductivity and superior high temperature stability. In this work, Bilayer La2Zr2O7 and conventional 8 wt% yttria stabilized zirconia (8YSZ) coatings were deposited using plasma spray technique. Both singlelayer La2Zr2O7 and double-layer 8YSZ/La2Zr2O7 coating architectures were designed. Thermal cycling and thermal shock tests were used to evaluate coatings’ thermomechanical properties. All La2Zr2O7 coats were delaminated in the furnace cycle test in less than 20 cycles. This is because residual thermal stresses accumulated during thermal cycling. In the jet engine thermal shock (JETS) tests, the SCL La2Zr2O7 and DCL dense 8YSZ/La2Zr2O7 coatings were fully delaminated. In contrast, the DCL porous 8YSZ/La2Zr2O7 coating sample only partially delaminated on the edge. This is because of the porous 8YSZ layer provides strain compliance. The findings will help to propose efficient thermal barrier coating systems.

Jan 1, 2016

The Institute conducts jointly with the American Society of Civil Engineers, American Society of Mechanical Engineers and American Institute of Electrical Engineers, certain activities as listed below, and is joint owner with them of certain properties. United Engineering Trustees, Inc. When Mr. Carnegie made his gift which made possible a home for the engineering societies, a separate corporation was organized to act as a holding company and to manage the common property. This was long known as the United Engineering Society, but the name has now been changed to one which more nearly reflects the real function of the corporation. It holds title to . the Engineering Societies Building and to various funds placed in its charge and is managed by a Board of Trustees, of which three are chosen by each of the four societies, American Institute of Mining and Metallurgical Engineers, American Society of Mechanical Engineers, American Institute of Electrical Engineers and American Society of Civil Engineers, which have equal and undivided interests in the property. The land and building cost two million dollars. During the year 1934, the Constitution and Bylaws of The United Engineering Trustees, Inc., were thoroughly revised and a better organization of its functions was affected: The Engineering Foundation and the Engineering Societies Library were made "departments" of the United Engineering Trustees. The Founders Societies share in the property which it holds, and estimated at the present time, as follows: Real estate, $1,987,793; Depreciation and Renewal Fund, $336,992. The U.E.T. has endowment funds-' amounting to $1,107,677. The A.I.M.E. trustees are W. D. B. Motter, Jr., A. L. .Queneau and Albert Roberts.

Jan 1, 1937

By John Cogan

INTRODUCTION Lake tapping is a method of blasting an intake into a body of water from below the natural water surface without first lowering that surface or installing a protective cofferdam around the tap hole. Lake taps are done by first excavating a tunnel almost to the water/rock contact and then blasting out the final protective rock plug at one time to allow water to suddenly inflow into the tunnel from the lake. This procedure can be done "dry" or "wet." In the dry method the tunnel is empty of water before the final plug blast while in the wet method it is partially filled with water. This paper describes a wet method lake tap as performed at Alaska Power Authority's Tyee Lake Hydroeletric Project in southeast Alaska. The Tyee Lake project is located approximately 40 miles southeast of Wrangell, Alaska, in a glacially formed valley called the Bradfield Canal. The project consists of a powerhouse located at sea level on the canal, a system of tunnels and shafts connecting the powerhouse to Tyee Lake at elevation 373 m (1225 ft), and an 129 km (80-mile) electrical transmission line leading from the powerhouse to Wrangell and then Petersburg, Alaska. Tyee Lake itself is a natural lake gouged out of the rock by glacial ice during the last ice age. The objective of the project was to tap into the lake and use the water as a source for power production. The techniques used for lake taps have been developed in Norway where conditions are favorable for their use in hydroelectric proj¬ects. Over 100 have been performed. In the United States the Tyee

Jan 1, 1984

By Filippo Maria Leoni, Alessandro Bertero, Gianluca Pianezze

"As part of the Southeast Louisiana (SELA) drainage program, designed by the U.S. Army Corps of Engineers (USACE) to reduce flood damages in the City of New Orleans and surrounding parishes through the construction of new pumping stations and better drainage canals, the SELA-22 project entailed the installation of a concrete covered canal along Jefferson Ave. and Prytania Street, in a highly urbanized portion of Uptown New Orleans, LA. The scope of the required soil improvement was to replace the soil between two parallel lines of sheet piles with a soil-cement mass to eliminate underseepage and provide structural support for the concrete culvert. The USACE selected the jet grouting (Jet Grout) technology for the construction of the bottom plug. The bottom plug is between 18 and 21.5 ft thick with a maximum depth of approximately 40 ft, for a total length of approximately one mile. The treated soil comprised soft clays and silts with occasional presence of sands. Project specifications required 100% area coverage, a 28-days unconfined compressive strength of 100 psi and hydraulic conductivity of 1x10-6 cm/s, to be verified by testing specimens from cored samples. The specialty geotechnical contractor proposed to accomplish the task utilizing their proprietary and innovative elliptical bi-fluid Jet Grout technology, and elected to perform a pre-construction bench scale laboratory mixing program to determine the most suitable grout mix features (i.e. binder type and proportions, binder content, etc.) to be applied in the subsequent field test and production stages. This paper will summarize and compare the results obtained from the different pre-construction and construction stages; interpretations of the data will be provided, along with general considerations regarding the effectiveness and significance of bench scale testing for jet grouting applications.INTRODUCTIONIn general, the effectiveness of the construction parameters in any ground improvement work depends largely on the physical and mechanical properties of the soil to be treated. Therefore, well designed laboratory and field test programs, aimed to disclose the interaction between the site-specific soils and the mixing parameters, are essential to achieve the desired end product."

Jan 1, 2016

By Sandeep Singh Sandhu, Karanvir Singh Ghuman, Manjit Singh

"Cobalt based super alloy stellite 6 was weld cladded on AISI 304 L stainless steel using SMAW process in order to improve the wear resistance for tyre crusher blades. Microstructure characterization and micro hardness testing was performed on stellite 6 cladding. The suitable parameters viz. 80 Amp current with arc weaving technique was selected by performing bead on plate experiment were further used for depositing multipass multilayer cladding to achieve full filler chemistry at the top surface. Further GTAW process was used for re-melting the top surface of the cladding. Comparative evaluation of the claddings showed that TIG re-melting resulted in increased microhardness and wear resistance in comparison to as cladded specimens even with lesser deposition of material. It was observed that TIG re-melting improved the hardness from 603 HV0.5 kg to 712 HV0.5 kg. Micro structures of stellite 6 contained cobalt solid solution matrix along with inter dendrite chromium carbides which resulted in the increased micro hardness values. Pin on disc abrasion tests were carried out at room temperature and the worn out surfaces were characterized using SEM and EDS.INTRODUCTIONThe crusher blades are used in many industries for crushing various types of material and its wider applications in tyre rubber crushing mills, metal-powder crushers industries etc. Most of the crusher blades are damaged by the wear and impact loading conditions. It is because of metal to metal abrasion and the temperature also plays a vital role in blunting the cutting edges of these blades. The wear is the major cause which leads to loss of material and thus the productivity that can never be recovered (Kotechi et al., 1992). The wear can be reduced by coating of various super alloys which could reduce the behavior of metal degradation even in aggressive environments. Cladding of cheaper low alloyed material with expensive superalloys to enhance the performance of components at low cost has been investigated by many scholars (Deng et al., 2010, Kennametal, 2007, Lolla et al., 2014, Singhet al., 2014, J.N et al., 2003, Ramkumar et al., 2012). Many researchers have reported that cladding is an application of build-up deposits of specialized alloys to resist abrasion, high temperature corrosion and impact loadings. Cladding is used for providing required mechanical strength properties as well as inhibition of oxidation and other corrosive degradation. Coatings are used to protect the heat affected areas like tubes of fluidized bed combustor etc. (Kirchbner et al., 2008, Wang et al., 1994, Hocking et al., 1993, Ananthapadmanabhan et al., 1991, Staia et al., 2001). Coating techniques are widely used for the protection of turbine engine and boiler tubes against high temperature corrosion attack, power generation equipment, chemical process equipment, aircraft engines, pulp and paper processing equipment, bridges, rollers and concrete reinforcements, orthopedics and dental, land-based and marine turbines, ships. Coatings of stellite 6 are widely used in steam turbine blades and boiler tubes for power generation because of an excellent combination of impact, wear and other properties. It can maintain its properties even at high temperature and in harsh environments (Kobayashiet al., 1999, Alam et al., 2009, Munehru et al., 2009). The loading and unloading conditions experienced by the material may induce the surface cracks which lead to its breakage and leaving large pits in the surface (Meng et al., 1995). Many researchers have reported that the properties of cladded layers can be increased by various techniques such as controlling the current variations, dilution, heat input, laser and other re-melting processes, addition of special alloying elements, speed of weldingetc(C.M Anaet al., 2002, Kumaret al., 1999, Luo et al., 2012, et al., Madadi et al., 2011, Shin et al., 2003, Kuzucu et al., 1997, Sudha et al., 2008, Sawant et al., 2017, Houdkova et al., 2016, Ciubo"

Jan 1, 2017