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By Mei Yang, Wei Gao, Jian Yang, Qingcai Liu, Wenchang Xi

"TiO2 has been loaded on cordierite porous ceramic to prepare the SCR catalyst carrier by using both APCVD and sol-gel technology. In APCVD method, TiC14 and O 2 were used as reaction precursor. TiC14 was gasified by using N2 as carrier gas which was controlled to 500sccm. Its reaction temperature and reaction time were limited to 773K and 30min respectively. The physical properties, SEM and SEM-EDX of the TiO2-cordierite carrier and the properties of SCR catalysts prepared by these carriers have been tested. The tests showed that TiO2 loaded by APCVD method were of graininess shape and even accumulation. The loading rate of TiO2 and the specific area of carrier sample were increased 114% and 21 % respectively comparing with sol-gel technology. In the result of sol-gel method, the maximal difference of Ti content was 66.92%, while the result of APCVD method was 18.89%. It demonstrated that TiO2 was uniformly attached with the cordierite ceramic by using APCVD method, which would ensure more active ingredients well loaded on the Ti02-cordierite carrier. This difference made the denitrification ratio of catalyst prepared by APCVD method was 8.1 % higher than that of catalyst prepared by sol-gel method.IntroductionIn recent years, the emission of NOx, which were caused by coal-fired power plants, has gotten more and more attention. SCR (selective catalytic reduction) is the most effective technology to DeNOx [ll. The core technology of it is the catalyst. The SCR catalyst usually uses Ti02 as the carrier, and V2O 5 as the active component [2, 3] . However, the thermal stability and mechanical properties of TiO2 carrier are unstable, which would influence the performances of the catalyst. The commercial catalyst generally uses WO3 or MoO3 to promote its heat stability at present [4-7] Besides, TiO2 is expensive. Compared with TiO2, the cordierite is of good thermal stability and lower price. So loading Ti02 on cordierite porous ceramic as carrier to produce SCR catalyst is of good prospects [S, 91 • Currently, TiO2 is usually loaded on cordierite by the sol-gel method. But some research has shown that the sol-gel method easily reduced the loading performances of TiO2, such as distribution, combination, etc. APCVD (atmospheric pressure chemical vapor deposition) has many advantages to preparing TiO2 films, such as high bonding strength, fast reaction rate and so on [l0-13l_ In this paper, TiO2 has been loaded on cordierite porous ceramic to prepare the SCR catalyst carrier by using both APCVD and sol-gel methods. The properties of the carriers prepared by the two processes have also been compared."

Jan 1, 2011

By Zirlene Alves da Silva Santos

O presente trabalho analisa as falhas por desgaste em um transportador de correia de uma empresa mineradora que beneficia o minério de ferro. O transportador de correia, por ser um equipamento critico em qualquer linha de produção, é o objeto do estudo de caso utilizado para o desenvolvimento do trabalho. O objetivo desse estudo é reunir informações a respeito dos desgastes que o transportador apresenta em um determinado período de tempo para criar uma tabela com os principais tipos de desgastes e a freqüência com que eles ocorrem. As falhas por desgaste são encontradas através da pesquisa documental pelo software Maximo e da análise feita no local do transportador. Como resultados das análises foi constatado que o desgaste predominante é o abrasivo por dois e três corpos, esse promove a perda gradual de material da superfície dos componentes do transportador de correia.

Aug 16, 2017

By Judson G. Brown

In order to filter small amounts of fine slimy solids the reversible cake-filtration process was developed. The filterable solids contents lion in feeds can range from less than 1 ppm up to about 5%. The relative advantages of this process, are usually the greatest in the range of 0.05% to 1.0% filterable solids. Filterable solids that average in particle size about 20 microns& are non-compressible are very easy for this filtration process. Some feeds have been all sub-micron in particle size. A 1/8 inch thick cake is considered to be very thick. The usual cake is between 13/2 and 1/16 inch thick. A new line of injection molded plastic filter plates were developed for use with the reversible cake filtration process. The first commercial sized installation of this system was made 3 years ago in the Wakefield Y.M.C.A. swimming pool. Over 70 filters ranging in size from one plate to 63 plates have been produced. In addition to the process advantages there are the low cost and corrosion resistance advantages of the plastic plates.

Jan 1, 1962

Gold has been known and mined in Australia for over 150 years. It occurs and is mined in all States and the Northern Territory. In the past 30 years approximately 8300 t of gold has been mined and gold exports have contributed over $106 billion to the Australian economy. In the first three quarters of the Australian financial year 2006 - 07 (ending 30 June 2007) gold exports were valued at $7.3 billion, which was 13 per cent of the value of all minerals exported and five per cent of AustraliaÆs total goods and services exports over the period. Clearly gold has been and remains a very important component of the Australian economy.

Jan 1, 2007

By P N. Holtham

Magnetic separation is routinely used in the processing of titanium minerals, and the efficiency of these operations can be determined by measuring the magnetic properties of the process streams. The valuable components in the feed to a titanium minerals plant have specific magnetic susceptibilities ranging from -10-9 m3 kg-1 (zircon) to 10-6 m3 kg-1 (ilmenite). However, in an industrial environment, in which the mineral temperature may range from 20 to 120¦C, it is difficult to measure susceptibilities lower than about 10-7 m3 kg-1. Hence laboratory testing of spot samples from magnetic separators is currently required to obtain accurate performance data. This is an inherently slow process and where feed grades are variable, optimum performance of magnetic separators is generally not achieved. This paper describes the development of an inductance-based instrument for measuring very low levels of magnetic susceptibility on-line. The signal from the instrument can be used for process control purposes to maintain optimum magnetic separator performance. A prototype instrument has been installed in the zircon scavenger circuit in an Australian titanium minerals plant. The circuit consists of a roll magnetic separator treating a feed consisting mainly of monazite and stained zircon. The monazite-rich magnetic fraction is returned to the mine site for disposal, while the non-magnetic fraction is recycled to the zircon wet circuit. Splitter positions in the separator are adjusted when the final zircon product fails to meet specification, or the magnetic fraction contains more than 30 per cent zircon. Weekly composite grain counts show that sub-optimal operation of the magnetic separator results in significant zircon losses into the magnetics fraction. Using the instrument, the zircon content of this stream can now be accurately determined from the measured magnetic susceptibility, provided a correction for the effect of mineral temperature is applied using the Curie - Weiss relationship.

Jan 1, 2001

By Robert H. Ridgway

This paper presents the results of the second in the series of annual canvasses on the consumption of ferrous scrap and pig iron in the United States, inaugurated in 1935 by the Bureau of Mines and published in Report of Investigations 3329. The study was undertaken in response to requests from trade organizations and others for detailed statistics on this phase of the iron and steel industry. Thus, for the first time, producers, buyers, sellers, and consumers of iron and steel scrap have had an accurate statistical picture of this important raw material As originally contemplated, the study was to be continued on an annual basis, but, owing to budgetary limitations for the fiscal year 1937-38, the Bureau may be unable to conduct the canvass for 1937.

Jan 1, 1937

By Santhanam Ramesh

"The shell (exoskeleton) waste of shellfish such as shrimps and crabs is the raw material in the extraction of chitosan, a polymer. Chitosan has several medicinal values such as reduction in cholesterol, urea and creatine in the blood. It is estimated that about 40000 tonnes of chitosan may be obtained from all chitin yielding invertebrate sources of India and a foreign exchange of 600 million US$ could be earned annually. Awareness has to be created among sea food processors to put up plants to convert shellfish wastes into chitosan. Similarly pharmaceutical industries may use chitosan in the development of new drugs. Types of training and awareness programmes to be organized for entrepreneurs, sea food processors and pharamacists are discussed in this paper.IntroductionIndia earns annually foreign exchange to the tune of 0.8 million US$ by exporting processed marine crustacean shellfish resources such as shrimps, crabs and lobsters (Figure 1) through 300 sea food processing industries. At present, only a small quantity of shell wastes (exoskeleton) generated from the above is utilized as an ingredient in fish feeds and hence much of the wastes are disposed off either as land fill or by direct dumping in sea. These wastes containing primarily chitin could be the major raw material for the production of a proteinaceous byproduct viz. chitosan, a highly valued pharmaceutically important source"

Jan 1, 2008

By Melvin W. Kraschnewski

In 1966 Central Ohio Coal Company and Bucyrus-Erie signed a contract authorizing Bucyrus-Erie Company to design and build a 220 cubic yard dragline. This dragline would be used for stripping overburden from their coal reserves located near Cumberland, Ohio. The size of the machine was arrived at after a thorough application study of their annual coal output requirement, depth of overburden and type of terrain. The design and construction of this machine which has been designated by BECO as model number 4250-W is the title of this paper. Size wise based on machine weight the 4250-W represents an increase factor of three over our largest current dragline. Probably the easiest way of presenting a machine of this size is to build it from the bottom up.

Jan 1, 1969

By Alan D. Smith

[A standardized checklist in a questionnaire format, was established to investigate selected factors associated with coal nips roof falls, as derived from an intensive review of the literature. A plot study was undertaken to aspect and explore possible statistical relationships that may exist with these parameters. the Purposes of toe study were to: 1. Study in a systematic and empirical fashion selected parameters that may be capable of differentiating characteristics of roof falls; 2. Obtain some predictive indices cased on selected physical and management related variables so that predictions of future problems associated with mine roof falls can be completed, prior to its actual occurrence. Accomplishment of these goals should result in valuable guides to the mining engineer in scheduling exploration work and 4 determining economic feasibility of certain ground control and .lining pro and practices. The parameters associated with mine roof failure that where included in the questionnaire are: working section, county, spar., orientation degrees), pillar dimensions width, length), seam thickness, roof fall dimensions (length, width, surface area, volume), shape of fall (arch, dome, laminar), thickness of thinnest immediate layer, lithology of the first four i.e.-diate roof layers, thickness of h e first four immediate roof layers, type of initial support systems before failure, type of resupport system after failure, length and spacing of bolts in use before failure, length and spacing of bolts planned after allure, presence of .cater, time failure after It coal excavation, distance t3rest ace, physical operation during, time of coo failure, location of the roof fall entry failure occurred ence of sloughing of ribs before failure, and presence of floor heave condition before failure. The typical roof fall had an average roof spar of 20.3 feet, -06 feet depth o coal seam, occurred 136 feet from nearest face, coal seam thickness of inches, p--ar :width off 45 feet surface area D' roof fall 1151 ft2, mainly lamin- shaped, previously rat fore fall between good to very good, little floor heave presence, usually cracks before the fall about 40 percent of reported cases, shales in most of the immediate layers, and usually located in an entry or intersection. in addition, multiple linear regression techniques were employed in the testing process of 18 major research hypotheses in a search for relationships among the various parameters studied of which were found to be significant, once corrected for multiple comparisons.]

Jan 1, 1984

By D. Spitty

There are enormous complexities with mine planning and the problem itself presents a huge challenge to the existing mine planners performing this activity. Mine planning optimization supports planners to determine ?What are the best increment excavation sequence and the best material blending combination such that throughput, quality, cost, utilization and Net Present Value (NPV) targets are met?? It is achieved through using an advanced scientific approach that has been specifically adapted to address the mine planning dilemma.

Feb 23, 2014

By César Jaime Fernández

El presente texto señala la función de la empresa privada en el desarrollo minero del Perú a través de dar a conocer los conceptos fundamentales que esto implica y asi determinar el crecimiento minero que convenga al país. Asimismo se revisa la evolución del hombre en la actividad económica, la empresa y los sistemas económicos, la empresa privada, la evolución en el Perú, la reforma de la empresa privada en el Perú y la responsabilidad social de las empresas en torno a la realidad peruana y el desarrollo de la confianza de parte de la comunidad en la inversión privada futura.

Nov 20, 1978

By Charles F. Hickey, Eric B. Kula

Thermomechanical treatments applied to the maraging steels include a) cold working in the austenitic condition at 650°F, followed by transformation to martensite and aging, b) cold working in the murtensitic condition and aging, and c) cold working in the aged condition with and without subsequent reaging. The strength increases in these steels are very small compared to the increases observed in conventional carbon and alloy steels. The changes that are observed are compatible with the strengthening mechanisms operative during thermomechanical treatment of conventional steels, however. Differences are caused by the absence of a carbide precipitate and the low work-hardening rate in both the solution-treated and the aged conditions. ThE 18 pct Ni maraging steels represent a class of steels which are finding great interest for high-strength applications.1~2 They are essentially carbon-free, and contain 7 to 9 pct Co, 3 to 5 pct Mo, and 0.2 to 0.8 pct Ti. Although austenitic at elevated temperatures, they can be air-cooled to room temperature to form a martensite, which because of the absence of carbon is relatively soft. On subsequent reheating age hardening occurs and strength levels of 250 to 300 ksi yield strength can be attained. These steels appear to be particularly suitable for studying the response to various thermome-chanical treatments for additional reasons other than the obvious one of attempting to improve their already attractive properties. Thermomechanical treatments can be defined as treatments whereby plastic deformation, generally below the recrystal-lization temperature, is introduced into the heat-treatment cycle of a steel in order to improve the properties. With an absence of intermediate transformation products on air cooling the maraging steels have good hardenability and hence can readily be cold-worked in the austenitic condition prior to transformation to martensite. Further, they can be worked in the martensitic condition prior to aging, and even can be deformed in the fully aged condition. Finally, it is of interest to compare their re- sponse to that of the more conventional alloy and carbon steels, where the role of carbides is important in the strength increase by thermomechani-cal treatments. The thermomechanical treatment of conventional steels has been the subject of a recent review.' I) MATERIALS AND PROCEDURE The steel used in this investigation was a commercially produced vacuum-melt heat, which had been rolled to 0.090 in. and mill-annealed. The composition of the alloy was as follows: 0.02 C, 0.08 Mn, 0.10 Si, 0.009 P, 0.009 S, 18.96 Ni, 7.34 Co, 5.04 Mo, 0.29 Ti, 0.05 Al, 0.004 B, 0.01 Zr, and 0.05 Ca. Unless otherwise stated the heat treatments used were the standai-d solution treatment at 1500°F for 1 hr, air cool, followed by a 900°F, 3 hr age. In this condition, the material exhibited 232 ksi yield strength and 239 ksi tensile strength. Mechanical properties were determined by Vicker's hardness measurement (20 kg) and by tensile tests on standard 1/2-in.-wide, 2-in.-gage-length sheet tensile specimens. Notch tensile tests were run using the 1-in.-wide NASA type, edge-notched specimen.4 Fracture-toughness determinations were made on 3-in.-wide, center-notched, fatigue-cracked specimens, following the recommendations of the ASTM Committee on Fracture-Toughness Testing.4 An electric-potential technique was used for measuring the crack size at the onset of rapid crack propagation5 which is necessary for calculations of Kc, the critical stress-intensity factor under plane-stress conditions. The critical stress-intensity factor under plane-strain conditions KI, was also calculated, using the stress at which the first observable crack growth occurred. 11) RESULTS A) Cold-Worked in the Austenitic Condition. The reported M, temperature for the 18 pct Ni maraging steel is about 310°F.1 Therefore, a temperature of 650°F was selected as suitable for rolling in the austenitic condition. Specimens were solution-treated at 1500°F for 1 hr, air-cooled to 650°F, and rolled varying percentages from 0 to 60 pct, at 20 pct reduction per pass. Tensile and hardness properties after aging at 900°F for 3 hr are shown in Fig. 1. The tensile strength increases from 253 to 271 ksi and the yield strength from 247 to 265 ksi as a result of a reduc-

Jan 1, 1964

US 4,189,461-Hydrometallurgical extraction of values from a sulfide ore of copper, silver, nickel, cobalt, molybdenum or zinc Ore is leached in a first stage with an aqueous nitric acid leach liquor and In a second stage the preleached mineral is oxidized with nitrogen dioxide to enable the metal values to be solubilized. The second-stage leach liquor is routed to the first stage, while first-stage liquor is subjected to electrolysis or other treatment for values This patent is a continuation- in-part of US Patent No. 4,132,758, dated Jan 2, 1979. R E Lueders and T C Franiewicz, assigned to Kennecott Copper Corp Feb. 19, 1980. 8 pp. (423-27). Filed. 2-23-78 (880,552). (Drawing below)

Jan 1, 1982

By S. N. Rossovsky

"A new method for the hydrometalfurgical treatment of refractory gold arsenosulphide concentrates is presented. Themethod involves a combination of' finegrinding, intensive agitation, flotation, and cyanidation, and consists of leaching of -10u pyrite and arsenopyrite particles in alkaline solution under intensive agitation without the application of costly high-pressure and roasting techniques. Consistent extractions of gold, in excess of 96%, are achieved.IntroductionConventional methods of alkaline leaching of gold arsenosulphide concentrates in an autoclave» and under electrochemical oxidation( 2) require expensive equipment as well as high-cost energy and reagents. In other cases, processing of gold concentrates inelude: ultra-fme grinding, calcination at 200°C to 250°C with the addition of an oxidant (NH4NOJ followed by alkaline leaching of the resulting calcine with hydrogen peroxide, the latter being a complicated method yielding poor extractions of gold (89% to 90%). In this paper, a hydrometallurgical method is described for processing refractory gold arsenosulphide concentrates in which alkaline leaching is followed by cyanidation of the residue."

Jan 1, 1993

By Y Akiti, J Moller, E Esper, R Rugolo, A Pains

"Morro do Ouro Mine is a high tonnage/low-grade mine located in Paracatu, Minas Gerais State, Brazil. The mines move around 55 Mt of ore per year at an average grade of 0.4 g/t. The auriferous mineralisation of Morro do Ouro is related to hydrothermal fluids rich in arsenic (As), gold (Au), lead (Pb) and zinc (Zn). These percolated along favourable structures contained within phyllites of Upper Proterozoic age and defined a mineralised megaboudin which outcropped with 4 km extension and up to 2 km in width. The litologies in the interior of this structure are typically more deformed, sericitised and sulfidised, and exhibit the development of quartz boudins in the centre of the more deformed zones where are found the higher Au grades and the coarser sulfide crystals. Gold is preferentially associated with arsenopyrite, mainly occurring in fractures or aggregations of crystals and is rarely in solid solution or refractory. Over 90 per cent of the gold contained in the sulfide ore is free or extractable by cyanidisation. The current mineral reserve is 17.9 Mt at 0.403 g/t published at the end of 2012.In order to get a good grade estimation that represents the orebody more accurately a solids methodology was used to distinguish the different orebodies. Before 2011 the orebodies were worked with two domains relating to the weathered mantle. The B1 ore, which is oxidised, is located at the top of mineralisation, and is used to feed Plant 1. Underneath B2 ore, which is fresh sulfide bearing, represents over 30 years of production in Plant 2.In order to improve the predictability of gold grade estimation in geological modelling and to get a better predicting behaviour of each domain on the deposit, studies were carried out in which it was possible to show a correlation between elements and the mineralisation. One strong correlation and spatial distribution between Au and As, As and sulfur (S), Au and Pb, Au and Zn were found.Based on geochemistry, mineral correlations, amount of sulfide, structural deformation, texture of sulfides and the daily experience of the mine, it was possible to create solids that individualised bodies with similar mineralogical and chemical characteristics using the parameters listed above.After 2011, a new modelling concept was proposed and built with 11 different domains, compared with the previous, and with two more parameters: recovery acid neutralised capacity (ANC).Each of these bodies have different behaviours in mineral processing, like flotation and metallurgy. For example, bodies with pyrrhotite bring problems in the flotation, bodies with high arsenic do not recover well, bodies with high As with coarse texture have good recovery, bodies with fine texture do not have good adherence in production.In the present state of knowledge, protocols are being developed for bench testing to predict the recovery of each geochemical domain aiming to include these in the geological model for the parameter recovery. It is intended to create a field throughput in the model of ounces per hour, from each block of each domain to better predict the production, using the parameter recovery, Au and Bond Work Index (BWI).CITATION:Esper, E, Rugolo, R, Moller, J, Akiti, Y and Pains, A, 2013. Morro do Ouro geological model with a metallurgical view, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013, pp 67-74 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Sep 29, 2013

By Gennaro G. Marino

This paper summarizes and evaluates data on mine subsidence ground movements and associated damage for houses in Illinois. Based on the data collected, the response of homes to subsidence ground movements is expressed in terms of repair costs. A damage criteria is then proposed that relates the ground movements and damage levels. The data were collected as part of a comprehen¬sive study performed for the Illinois Abandoned ?Lined Lands Reclamation Council, A -M-RC, by the Civil Engineering Department at the University of Illinois, and probably will be published in late 1934 by the council. The study concentrated its efforts on surface ground movements and the effects to houses over abandoned room and pillar mines. The resultant surface subsidences are commonly dish or bowl shaped and are termed sags. Method of Analysis The steps in analysis used to arrive at the proposed damage criteria are: 1. Canvas and rap subsidence damage in houses, 2. Assess the associated ground movements, 3. Estimate the damage repair cost, 4. Develop a damage/repair level classifica¬tion, 5. Correlate the associated ground movement, damage/repair level and home construction type, 6. Propose a damage criteria.

Jan 1, 1984

By Frederico Ibrahim Horta

As estradas de mineração influenciam diretamente nos custos de operação de mina e manutenção de equipamentos. A equipe de planejamento de lavra em conjunto com a equipe de operação de mina buscando a melhoria de seus indicadores de custos e produtividade realizaram várias melhorias no perfil de transporte da Mina Oeste. Para realização deste trabalho foram mapeados e projetados novos trechos da mina que poderiam ser melhorados em termos de inclinação de rampa, subidas, descidas e curvas. A realização destas melhorias, em conjunto com correções de drenagem e forragem das pistas, possibilitou a alteração do limite de velocidade dos caminhões fora-de-estrada em alguns trajetos de 40 para 50 km/h. Como resultado destas alterações, obteve-se um ganho de 18% na produtividade da frota de transporte e uma redução de 13% nos custos de operação.

Oct 30, 2017

By L. Martins

To increase zinc recovery in the concentrate, this investigation performed mineralogical characterization, dispersion studies, bench and pilot-scale flotation experiments and an industrial flotation trial. The objective was to verify the flotation behavior of the silicate zinc ore (calamine type) in the presence of slimes, with the aid of dispersing agents. Characterization studies identified the major minerals in the flotation feed as hemimorphite (calamine), quartz and dolomite. Dispersion tests showed that enhanced dispersion of the particles in the pulp in the absence of reagents occured at a pH range between 8.5 and 12.0. Bench-scale flotation experiments were planned using the statistical tool of complete factorial design at two levels, replicated once. These experiments showed, and were confirmed at the pilot-plant scale, that higher doses of sodium sulfide and polymeric dispersant combined with sodium silicate favored a higher metallurgical recovery. At 6,800 g/t (218 oz/st) sodium sulfide and 6,992 g/t (224 oz/st) polymeric dispersing agent combined with sodium silicate, a zinc grade of 38.4% in the final concentrate was achieved, at an average metallurgical recovery of 72.4%. The industrial trial confirmed the pilot scale results, leading to zinc recovery of 76.1% and a 37.3% zinc grade in the concentrate. Key words: Froth flotation; Flotation reagents; Flotation depressants; Zinc/ zinc ores

Jan 1, 2010

NEW MEMBERS The following list comprises the names of those persons who became members during the period Nov. 10, 1916 to Dec.10, 1916. BARNSDALL, THEODORE N., Treas. & Mgr., Highland Gas Co., 24 West Corydon. St., Bradford, Pa. BEASLEY, FRED E., Asst. Supt., Copper Refinery, Consolidated Mining & Smelting Co., Trail, B. C., Canada., BREWSTER, THOMAS T., Vice Pres., Gen. Mgr., Mt. Olive & Staunton Coal CO., 1012 Federal Reserve Bldg.,-St. Louis, Mo. BRINDLE ARTHUR ST. C.... Mining Recorder's Office, Trout Lake, B. C., Canada. BULLOCK, Harry E., Pres Kentucky-Jewel Coal Co., Lothair, Ky. BUTLER, PERCY BENNETT, Mine Operator :..P. 0. Box 335, Joplin, Mo. BUTLER, ROBERT S Supt., Three Johns Mining CO., ,Joplin,.Mo. CABOT, Godfrey, L., Carbon Black Maker, Gas Engr., 940 Old South Building Boston Mass.

Jan 1, 1917

By Laura Pires Ribeiro Martins

Para a produção de peças e componentes automobilísticos, a utilização de ensaios não destrutivos é de grande importância, tanto para a detecção de defeitos como para a estimativa de propriedades físicas e mecânicas. Este estudo tem como objetivo avaliar dois métodos de ensaios não destrutivos (frequência de ressonância e ultrassom) através da determinação do módulo de elasticidade e do amortecimento de vibrações, em ferros fundidos vermiculares de classe FV 450. Estas técnicas também foram avaliadas para identificar a presença de microporosidades de contração na solidificação. Verificou-se que estas metodologias permitem estimar valores de módulo de elasticidade com bastante precisão, superior à obtida com ensaios de tração. Comprovou-se ainda que a capacidade de amortecimento de vibrações, avaliada pela taxa de atenuação da oscilação, é sensível à presença de interfaces na microestrutura do material, bem como à presença de pequenas porosidades.

Aug 16, 2017