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By C. J. Hartley

"Scandium oxide can be recovered as a by-product from process streams in a number of chemical and metallurgical plants including TiO2 sulphate pigment, Ni/Co laterite, zirconium oxychloride and uranium operations. The feed materials available for processing can be either mid or end of process streams containing many species in solution. This paper describes the strategies available to limit coextraction of elements into scandium containing streams from TiO2 pigment production and the removal of these elements to deliver high purity scandium oxide.A critical part of process development is to work within the constraints of the main process in terms of introducing new unit processes and producing minimal additional process intermediates and residues. This requires flexibility in designing flowsheets and plants to find novel process routes that avoid production of intermediates and/or the introduction of reagents that can compromise the main process operations.Bloom Energy has developed novel solvent extraction processes for the extraction and refining of scandium oxide that minimise impacts on core process streams within TiO2 pigment plants. The additional unit processes are designed to have minimal contact with pigment plant process streams to produce a concentrate that is refined to nominal 3N purity scandium oxide in a simple, small scale commercial plant."

Jan 1, 2016

By F. C. Grensing, W. R. Crib

Copper-15 Nickel-8 Tin alloy is a relatively modern material, having been discovered in the 1970’s. It has complexities with casting, hot working and interdependent solid state phase transformations. A key to the high reliability manufacture of wrought rods, bars, plates and tube is the casting technology, which limits segregation, promotes microstructural uniformity and enables hot working. The EquaCast® continuous casting process has enabled the production of a broadening variety of wrought forms with typical yield strengths ranging from 100 to 180 ksi (690 to 1241 MPa) depending on size, shape and temper. This paper reviews the characteristics of wrought Copper-15 Nickel-8 Tin products which have registration in AMS specifications (4596 and 4597) and MMPDS-04 (CN-1) for use in aircraft. The design limits, microstructures, fracture characteristics and tribological behavior will be examined. This alloy system is emerging as a material of choice for aircraft bearings, corrosion resistant oil and gas exploration components, machinery and demanding off-road equipment applications. ToughMet® 3 is an alternative or upgrade to conventional moderate and high strength aluminum bronze bearing alloys.

Jan 1, 2010

By Sazol Das, Hany Ahmed, Ganesh Bhaskaran, Zhuoru Wu

"Friction stir welding (FSW) process in lap configuration for dissimilar materials has been developed and tested for steel to aluminum joining. A novel cylindrical tool was designed for improved material flow. The joining of steel to high strength 5xxx and 6xxx aluminum was carried out by FSW technique using optimized process parameters. The microstructure, micro-hardness, joint strength and corrosion properties at the weld interface have been investigated. Optical and scanning electron microscopy reveled a well layered structure at the interface and lap shear tests of the welds showed excellent fracture resistance. Neutral salt spray tests for up to 500 hours (ASTM B117) were carried out on the bare steel to aluminum FSW joints, which did not show neither evidence of corrosion at the weld interface, nor any degradation of the weld strength. The FSW lap configuration was applied to prototype commercial vehicle structural component whereby a steel stiffener insert was friction stir welded to high strength 6xxx aluminum alloy. The interface microstructure showed layered root without any steel shattering in aluminum side. A finite element study was carried out to quantify the benefits where it was found that the stiffness increases by 76% under bending loads and 36% in torsion loads.INTRODUCTION Energy preservation and environmental issues, namely carbon footprint and legislation around emission in transportation industries has led to a growing need to use of lightweight materials such as aluminum and magnesium alloys along with various grades of steel in structural application, while still maintaining their strength and crashworthiness. Assembling dissimilar materials within integrated structure is thus a stringent requirement related to optimum performance. In order to achieve an efficient technology of joining dissimilar materials such as aluminum to steel, it remains difficult to select an effective welding process for a given joint configuration. The use of aluminum in transportation industries for structural component is not exclusive in a design and is almost always used along with various steel grades for a mixed materials solution, thus dissimilar aluminum/steel lap joining is of great interest since this is widely used in the assembly of parts (e.g. pillar, frame rails, chassis, body in white (BIW), CAB, etc.)."

Jan 1, 2018

By Roy S. Celland, K. H. Singh

The introduction of 'post' pillar mining at the Strathcona mine represents a new approach to ground support in cut-and-fill applications. The method has also shown significant economic advantages. It is believed that the development of this concept is one of the few examples where rock mechanics principles have successfully been applied in the development of a stoping method. The paper describes the evolution of this method and contains discussions on the theoretical analysis of the technical, operational and economics aspects of the system. Pillar design procedures and field observations on the practical application of theoretical analysis are also outlined.

Jan 1, 1973

By I. Cotman

Dimensional stone processing has become an important part of the world extractive industry, and today?s total stone block yearly production is estimated to be around 134.000.000 tons and is still growing by an average yearly rate of approximately 20%. In future, the same production will become an important part of the mining industry and presently, in some countries it represents even the main mining output. New environmental regulations, together with landscape and nature conservation requirements, create a number of difficulties in setting up new open pit dimensional stone quarries. As a result, many dimensional stone producers have recently started to apply underground techniques in order to produce the ornamental stone blocks intended for further processing. Underground production of stone blocks requires special mining methods and so far it has not been a cost-effective excavation method for all types of rocks. Presently, this type of stone excavation is generally applied in sedimentary and marble deposits because the rock has small to no mineral quartz content. When starting a new underground dimensional stone mine, it is necessary to analyse the impact of all primary factors which are crucial to set up a technically and cost effective advanced underground dimensional stone mine. The role of physical and mechanical properties of the rock, geological conditions, mineralogical composition, micro-tectonic state of the site, rock mechanic conditions on the site, durability and saw ability of the stone are decisive factors in foreseeing the future methods of extraction. The laboratory research work as well as the field work, is very important in decision-making aimed to choose the future excavation method. Also of equal importance is the serious market research, because it renders the indication of selling price potential. Having obtained the results from both types of research, mining engineers can design the mining methods which optimize financial return to the mine. The practice approved by 15 years of testing in the underground limestone quarry of Kanfanar gives future producers very useful advice and general data to facilitate the process of exploration intended to establish new similar underground quarries.

Aug 1, 2013

By A. H. Lang

"The name Barkc:rville district is applied loosely to the gold-bearing area around the historic town of Barkerville; the first mining camp in western Canada. The region is partly in the Cariboo mining division and partly in the Quesnel mining division. It contains two producing lode gold mines; the Cariboo Gold Quartz and the Island Mountain; and numerous other deposits. The regional structural pattern is outlined in this paper; the structural details of the producing mines are described in the papers that follow.The discovery of rich placer deposits in this district in 1860 was followed by the Cariboo gold rush. Placer mining in the area flourished until 1875 and then declined as the shallow diggings were exhausted, but important operations are still active. The total placer production amounts to about $50,000,000. An extraordinary number of quartz veins outcrop in the district, but many have only a small gold content. The miners soon recognized that the placer gold must have been derived from the erosion of these veins, and some directed their attention to the possibility of quartz mining. The erection of a 4stamp mill in 1876 was the first attempt at ore reduction in British Columbia, exclusive of arrastras. Efforts to mine the Cariboo lodes on a large scale were not successful, however, until 1933, when, due to the pertinacity of F. M. Wells and to the increased price of gold, the Cariboo Gold Quartz mine commenced production, followed by the Island Mountain mine in 1934. This success led to development work at many properties in the district, but the only ones that have reached production to date are the Columbia Tungstens, where scheelite has been mined intermittently since 1937, and the Cariboo Hudson, from which gold was produced in 1938 and 1939."

Jan 1, 1954

By D. F. Kidd

Introduction In a companion article, Surveys at Great Bear Lake, 1931, R. C. McDonald has described the general character, topography, and climate of the Great Bear Lake-Coppermine River area and the main means of access (l). The present paper will largely be confined to the geological features of the district. In the last two years, the rocks of the region have received considerable attention, and papers including references to .the geological succession have been written by Knight(2), Duncan(3), Norris( 4), Reid(5), Cameron(6),and Kidd(7). The writer confined his field-work during the 1931 season to the district between LaBine point and Hunter bay and northwest to the head of McTavish arm. Brief trips were made down the Sloan river from McLaren lake, 25 miles northeast of Hunter bay, to that place, to Dowdell (Sixty-six) point, the south point of Echo bay, and to the region north of the Dismal lakes and west of the Coppermine river. The inner part of Echo bay, which is the area discussed by Reid and Cameron, has not been seen by the writer and the geology there will not be discussed.

Jan 1, 1932

By I. Filzwieser, A. Filzwieser

The Peirce Smith converter is the key metallurgical vessel in the majority of copper smelters. During the two step process, oxygen enriched air is injected through a row of tuyeres into the matte received from a primary smelting unit. Additionally, in the first step the iron content is oxidized into a fayalite slag by the addition of silica. During the second step, the remaining copper sulphide is converted into blister copper with a final sulphur content of approximately 200 ppm. The overall efficiency of this process is determined by the total reaction time, the slag quality and quantity, and the chemistry of the final blister copper. To increase the reaction kinetics during both stages, the METTOP Process Control and Regulation (MPCR) system was developed, which consists of four elements: OPC - Optical product control ACR - Automatic computer regulation GCU - Gas control unit GIS - Gas injection system The OPC system from SEMTECH records the optical spectrum emitted by the off gas flame providing immediate, detailed process information. Using this online data, additional gas can be automatically injected into the converter through a gas injection system opposite the tuyere zone. An improved oxygen distribution in the melt and the accurate determination of the process end point results in a significant reduction in the process cycle time. Furthermore, by maintaining the reaction closer to the equilibrium the final sulphur and oxygen content can be reduced compared to the conventional process. In particular, the final sulphur content can be lower than 70 ppm, eliminating the need for an oxidation step in the anode furnace.

Jan 1, 2007

By D. F. VanDine

The phases of a typical exploration program for sand and gravel resources include: (1) collection and assessment of existing information; (2) air photo interpretation and remote sensing; (3) ground investigation and mapping; (4) sampling and testing; and (5) data storage, retrieval, analysis and presentation. Depending on the purpose, time frame and funding available for the study, these phases, and the various techniques used within each phase, will vary. Once a sand and gravel deposit has been located, defined in size and quality, and found to be suitable for a given purpose, it can then be classified as a granular resource.

Jan 1, 1984

By A. A. Holland

Introduction The world's largest known deposits of natural sodium sulphate (Glauber salt), generally termed 'alkali ' throughout western Canada, are located in the Province of Saskatchewan: reserves are estimated to exceed 200,000,000 tons. These are surface deposits resulting from the recent or present-day natural evaporation of brines, in which respect they are similar to those occurring in certain other parts of the world, as in semi-arid sections of the United States, Russia, Germany and Austria. In some areas, underground deposits formed hundreds of thousands of years ago have been _encountered in drilling, and indications are that they also were formed under arid or semi-arid conditions. The master key to the formation of deposits of natural sodium sulphate, wherever they occur, is a climate, either past or present, under which evaporation exceeds precipitation over a considerable period of time. Commercial development of the Saskatchewan deposits began about thirty years ago. Previously, the demand for sodium sulphate had largely been met by salt cake produced as a by-product in the manufacture of hydrochloric acid from common salt. The rapid increase in the production of Kraft paper and, more recently, the development of synthetic detergent materials, have caused a marked increase in the market for sodium sulphate. This chemical gives the extra toughness to Kraft paper and is used in detergent compositions in proportions as high as 75 per cent. Saskatchewan now has six commercial plants producing natural sodium sulphate. Production from each in the fiscal years 1947 and 1948 is shown in Table I. The newest and latest plant is that of Saskatchewan Minerals, at Chaplin, which 1s designed to produce up to 150,000 tons of salt cake, 98.5 to 99.5 per cent pure, yearly. This is equivalent to about 24 percent of the total United States production of crude commercial salt cake for 1947.

Jan 1, 1949

By Mostafa Benzaazoua, Emilie Ré, Raphaël Mermillod-Blondin, Hassan Bouzahzah, Jean-François Wilhelmy, University of Québec in Abitibi-Témiscamingue

"We analyzed two copper and lead flotation concentrates from the LaRonde mill using MLA technology (Mineral Liberation Analyzer) to identify the contaminants and to quantify their size and liberation. The MLA mineral quantification was compared with traditional mineralogical techniques (Scanning Electron Microscopy, Optical Microscopy, X-Ray Diffraction and Chemistry). The accuracy of MLA data was then quantify in application to metallurgical decision (mineral identification, mineral quantification, particle sizing and liberation quantification). We prepared five well-known materials from pure minerals and analysed them by MLA. MLA concentrates analyses showed the lead concentrate is mainly contaminated by pyrite and sphalerite. These minerals are liberated above 70 % and present a floatable size around 15 to 35 µm. Surface activation by dissolved lead from galena is therefore assumed for these contaminants. The analyses of the known samples show that mineral quantification and size distribution given by the MLA are consistent with the chemical analyses and the laser particle sizer. The liberation measurement is affected by the stereological effect. Modelling quantifies the overestimation of the particle liberation. Based on the modelling, the stereological shift on liberation should not impact metallurgical conclusions on the concentrate contaminations.INTRODUCTIONTo face the diversity of mineral processing challenges, the process mineralogy includes phase quantification, measurement of mineral size, liberation by exposure and by grade, association, surface contact proportion and texture. In the last decades, two SEM commercial tools emerged: MLA and QEMSCAN R. Both are based on specific combinations of backscattered electrons and X-ray images as well as image analysis routines developed at CANMET (Petruk & Pinard, 1976, Petruk, 1989), CSIRO (Frost, O'Hara, Suddaby, Grant, Reid, Wilson & Zuiderwyk, 1977, Reid, Gottlieb, MacDonald, & Miller, 1984) and JKMRC (Hall, 1977, Gu & Sugden, 1995). Recently, TIMA (TESCAN) and Mineralogic MiningR (ZEISS) supplied automated mineralogy for mining industry (Bouzahzah, Benzaazoua, Graham & Cropp, 2015, Gottlieb & Dosbaba, 2015a). In parallel, home-made routine were developped to resolve mineralogy challenges in mineral process but also in geometallurgy and mining environment (Kahn, Mano, & Tassinari, 2002, Knight, Klassen & Hunt, 2002, Mermillod-Blondin, Benzaazoua, Kongolo, de Donato, Bussiere & Marion, 2011, Hunt & Bradshaw, 2015). SEM mineralogy become essential to operation by setting units on mine sites (MacDonald, Latti, Adair, Bradshaw, & Dunn, 2011, Goergen et al., 2013, Dobbe et al., 2014, Gottlieb & Dosbaba, 2015b)."

Jan 1, 2016

By A. I. Collins, D. Danninger

Newmont has installed advanced control and online optimization on the dry grinding circuit and both roasters on its Carlin Trend refractory ore treatment plant. Subsequently, Newmont has developed a master plan for institutionalizing advanced control and optimization on all its processing units. Newmont is committed to a program of applying advanced control and optimization from crushing of ore to pouring of gold. This paper describes Newmont's experience with implementing advanced control and optimization and the benefits received. In addition, identification of advanced control and optimization opportunities and their economic justification is discussed.

Jan 1, 2005

By Clifford S. Gibson

A year ago a paper (1) was presented at the Annual Western Meeting of the Institute regarding silicosis in Ontario mines. It described the whole problem as we see it and discussed the means of prevention. The work and aims of the Technical Silicosis Research Committee of the Ontario Mining Association, and of the Committee's field engineer, were fully described also and it is suggested that reference be made to this paper in order to have a better understanding of the observations which are presented now. These observations enlarge upon parts of the dust control measures already discussed and tell of general progress in the past year. They concern fifty properties, the majority of the operating mines, which vary in size from the hopeful prospect to established producers yielding 11,000 tons of ore daily. Most of these are gold mines; a few copper-nickel. The ores range from heavy sulphides to siliceous materials and they are mined by many methods from varying types of deposits. The majority of the latter are steeply dipping and all are found in Precambrian host-rocks. Up to the present, die greatest depth to which mining has penetrated is 6,400 feet.

Jan 1, 1939

By M. R. Coffin

Since the plant startup in 1972, the leaching and jarosite precipitation circuits at the zinc plant of the Kidd Metallurgical Division have been reconfigured several times to improve overall performance, and/or to respond to market conditions. For the most part, the circuit changes have been driven by two market factors: the price of zinc and the price of silver. Until recently, circuit modifications undertaken to improve zinc extraction and recovery came at the expense of silver recovery, and vice versa. In 2004, the plant was modified once again to produce a precious metals-bearing residue, but additional leaching circuits were added to ensure that zinc extraction and recovery did not suffer as a consequence. The development of the zinc plant of the Kidd Metallurgical Division is updated in this paper, with a focus on the recent circuit modifications and associated control strategies that were implemented to maximize zinc and precious metals recoveries, and control the quality of the jarosite residue.

Jan 1, 2006

By M. A. F. Fedikow, D. A. Baldwin, C. Taylor

The Agassiz Metallotect and the Johnson Shear Zone represent two metallogenetic fea tures located within the northern and outhern belts, respectively. of the Aphebian-aged Lynn Lake greenstone belt in northern Manitoba . Numerous gold occu rrences are associated with these two regional features . The tratabound Agas iz Au-Ag deposit with 2.9 million tonnes of 5.2 g/tonne Au and 11.8 g/tonne Ag. occurs within the Agassiz Metallotect. The stratigraphic sequence characterizing the Agassiz Metallotect comprises interlayered ox ide. silicate and sulphide facies iron formations, biotite-rich and siliceous siltstones. and a high Mg- i-Cr basaltic rock that ha previou ly been identified as tholei itic picrite. These rocks can be traced in outcrop and by their INPUT and gradiometric signature for 65 km. The Johnson Shear Zone is an ill-defined 35 km long zone of strucwral disruption that crosscuts volcanic. sedimentary and intrusive rocks and contains numerous vein-type gold occurrences. Both of these metallotects are characterized by their low level of exploration activity and as a result offer excellent residual exploration potential. Rock, basal till and vegetation geochemical techniques applied in the vicinity of the Agassiz deposit indicate the presence of trace element dispersion halos associated with the mineralization. The halos define an exploration target larger than the mineralized zone. Gold occurrences within the two metallotects are described with emphasis on the Agassiz Au-Ag deposit . A wide range of gold occurrence-types is documented including syngencticstratabound , epigenetic-replacement and epigenetic-quartz vein .

Jan 1, 1986

By J. B. Mawdsley

Introduction The writer was instructed to visit the Chibougamau region during the field season of 1927 and report on the mineral discoveries that had been made there since 1911. lt was deemed advisable to obtain detailed information regarding the rocks underlying the area in the vicinity of these recent discoveries. Accordingly an area 60 square miles in extent was mapped. The outcrops were studied along the water courses and along bush traverses spaced at half-mile intervals between these water courses. The completion of the rest of the summer's programme allowed only three weeks for this work. lt is from this small, mapped area, and this necessarily cursory survey, that the material for this paper was obtained. Location And Means Of Access The name Chibougamau district is applied loosely to an ill-defined area of about 1,000 square miles lying mostly north and west of Chibougamau lake in the Province of Quebec. The lake is approximately half way between lake St. John and James bay. It lies 150 miles north of the Canadian National railway and 40 miles south of Mistassini?lake.

Jan 1, 1928

By G. S. Farnham

Abstract This paper lists the interests of the Physical Metallurgy and Chemical Research laboratories of the Metallgesellschaft, which were visited by the authors, members of a group of Canadian investigators sent to Germany by the Department of Reconstruction in 1945. The Physical Metallurgy Research Laboratory The following information was obtained from Professor E. Schmid, Chief of the laboratories. It is understood that Dr. Schmid is a former Nazi and was to be removed from his post in November (1945). Aluminium Research The laboratories investigated the corrosion resistance of the high-strength aluminium-magnesium-zinc alloys. The same test procedure as used by V.L.W. was followed and Dr. Schmid co-operated closely with Dr. Brenner on this project. Intercrystalline corrosion was combatted by additions of chromium, titanium, or vanadium, and the work in this field parallels that of Dr. Brenner of V.L.W. * Dr. Schmid reports that Bollenrath and Siebert believe that corrosion difficulties with these alloys can be overcome to some extent by heat treatment. He himself was of opinion that the correct answer lay not only in correct alloying but also in correct heat treatment. The heat treatment involved either interrupted quenching or a change in quenching rate from a solution temperature of 500°C. The procedure is either a slower cooling from solution temperature or an interrupted cooling with a holding period at l50°C. Work had been done on piston alloys, the 11-13% Si, 1% Ni, 1% Cu, and 1% Mg being the favoured material. This is called Lo-Ex and is similar to Mahle 124 or KS1275.

Jan 1, 1946

By R. E. Whitehead, G. J. Prior

"Abstract -Biotite from aplite that appears to have crystallized simultaneously with disseminated Cu-Mo mineralization at MacLeod Lake in northern Quebec yields K-Ar dates in the range 2032 ± 44 Ma to '2f1:)1 ± 47 Ma. The mean value, 2065 Ma, is some 400 Ma younger than the 2485 ± 64 Ma date obtained from a hornblende concentrate separated from a granodiorite sill that is spatially, but apparently not genetically, associated with the disseminated Cu-Mo deposit. The mean biotite date of 2065 Ma at MacLeod Lake, a K-Ar date of 2055 Ma reported from an area 50 km east of MacLeod Lake and published dates of about 2000 Ma for galenas from the Chibougamau Cu-Au ores, suggest a widespread thermal and mineralization event, in that part of the Superior Province east of James Bay, that differs from the common late Archean mineralization that is related to volcanism and metamorphic-intrusive activity.Sommaire - Les datations au K-Ar sur des biotites qui auraient cristallisé en même temps que la minéralisation disséminée en Cu et Mo dans une aplite mise en place au Lac MacLeod, au nord du Québec, s'échalonnent entre 2032 ± 44 Ma et '2f1:)1 ± 47 Ma. La datation moyenne, soit 2065 Ma, est d'environ 400 Ma plus récente que la datation obtenue pour un concentré de hornblende extrait d'un fùon-couche de granodiorite qui est spatialement mais ne serait pas génétiquement as­ sociée à la minéralisation disséminée en Cu et Mo. La datation moyenne de la minéralisation au Lac MacLeod, soit 2065 Ma, la dataion au K-Ar à 2055 Ma citée pour une région à 50 km à l'est du Lac MacLeod, de même que les datations d'environ 2000 Ma établies pour des galènes qui se trouvent dans le minerai aurifère et cuprifère à Chibougamau, suggèrent un phénomène thermique répandu qui aurait produit la minéralisation dans cette région à l'est de la Baie James, dans la province du lac Supérieur. Ce phénomene serait différent de celui qui aurait produit la minéralisation répan­ due d'âge archéen tardif qui elle serait associée à l'activité volcanique et à l'activité intrusive accompagnée de métamorphisme."

Jan 1, 1992

By F. Chiesa

Forty aluminium A356 castings were poured on a Low Pressure Permanent Mould industrial machine, 500x700mm in platen size. The 152mm wide casting comprised three steps, 25mm, 13mm, 6mm in thickness and a 2.5mm overflow which allowed to assess the thin wall capability of the process. The casting campaign, which produced 40 parts, allowed to test the influence of various production parameters including the time of application of the pressure in the crucible, artificial cooling of the mould and casting rate. The thermal history in the mould was recorded over the 40 cycles, which allowed to construct a reliable thermal model of the mould/casting assembly. The metallurgical quality of castings representative of the various conditions was assessed in the 25mm, 13mm and 6mm plates. This included measuring the level of microporosity, the dendrite fineness (DAS), along with the tensile properties in the T6 condition. The radiographic quality per ASTM E155 was also determined. Modelling filling and solidification allowed to verify the validity of the predictions based on available relationships relating microporosity, secondary dendrite arm spacing (DAS) and local tensile properties (Quality Index, Q) to the local thermal solidification parameters.

Jan 1, 2007

By Jan Kvinge, Aina Opsal Bakke, Yanjun Li, Jan-Ove Løland, Svein Jørgensen

"Compound casting is a very attractive approach to reduce the weight of components for some specific applications while keep both the functional and the mechanical property requirements. In this work, Al-7Si-Mg alloy /copper compound castings were produced through a low pressure die casting process. To reduce the oxide present in the interface, flux coating of the copper pipes was tested. The interface layer formed between the two alloys was investigated using Optical Microscopy (OM), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS). Vickers Micro-hardness was also measured across the interface. Results showed that the flux coating prevented the formation of the metallic bond between copper and aluminum. Instead, high concentrations of potassium, magnesium and fluoride, coinciding with formation of KMgF3 and MgF2, were detected in the interface. In the castings without surface treatment, a continuous metallurgical bond was achieved. In the bond layer, various Al-Cu intermetallic phases have been detected. In addition, formation of primary silicon particles in the reaction layer was observed in all castings. The mechanism for the formation of the intermetallic phases and the strength of the interface layer have been discussed.INTRODUCTION Recent development in the automotive industry has focused on producing lightweight components, which can reduce CO2 emission and increase the efficiency. Often, one material alone is not able to meet the requirements for a specific use. The need for lightweight bimetallic components has therefore increased. Aluminum-copper bimetallic components can be used in wires and bus bars where conductivity is an important factor (Lee, Bang, & Jung, 2005). Compared to Al-Cu alloys, Al-Cu bimetallic components can reduce both weight and cost without reducing electrical and thermal conductivity (Sheng, Yang, Xi, Lai, & Ye, 2011). A challenge is, however, that aluminum and copper have high affinity to each other, especially at elevated temperatures. This causes formation of brittle intermetallic phases with high electric resistance (Liu, Wang, Sui, Wang, & Wenjiang, 2016). In addition, both metals are subjected to oxide formation on the surface. Copper is especially exposed to oxidation at elevated temperatures (Pinnel, Tompkins, & Heath, 1979), while a thermodynamically stable oxide layer will spontaneously form on the aluminum surface (Papis, Loeffler, & Uggowitzer, 2009). Oxides are known to be passive substrates, which will reduce wettability and will thus prevent the formation of metallic bonding between aluminum and copper (Papis, Hallstedt, Löffler, & Uggowitzer, 2008)."

Jan 1, 2018