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By M. Noaparast, N. Nickoletopoulos, André R. Laplante

"This paper presents an application of the use of synthetic ores to study gold recovery by gravity. Three case studies are presented: the first focuses on the use of tungsten to study applications of Knelson Concentrators for upgrading gravity concentrates; the second on tungsten again, in this case to study the performance of a 86 Falcon Concentrator; and the third on lead to mimic gold's grinding behaviour.It is shown that the use of synthetic ores with metallic substitute for gold is not only expedient, but it can also lead to an increased understanding of separation and grinding mechanisms, because of the more accurate results and controlled particle shapes. The case studies highlight the problems associated with gold particle flakiness and gangue density. The grinding behaviour of malleable materials is shown to be complex, as particles can migrate to coarser size classes by flattening and cold welding, and to finer size classes by folding and actual breakage.IntroductionThe title of this contribution is not entirely misleading. Mineral processing has much to do with philosophy, rather Philosophy, as described by Georgius Agricola:""Furthermore, there are many arts and sciences of which the miner should not be ignorant. First there is Philosophy, that he may discern the origin, cause, and nature of subterranean things; for then he will be able to dig out the veins easily and advantageously, and to obtain more abundant results from his mining. ""1"

Jan 1, 1995

"AbstractThe Sedimentary Basin area of Western Canada, which lies between the Precambrian Shield and the Cordilleran mountain area, covers approximately 800,000 square miles. Sediments ranging in age from Cambrian to Tertiary are present and, of these, horizons in the Upper and Lower Cretaceous, Jurassic, Mississippian, and Devonian have yielded commercial oil and gas flows. Producing horizons in the Cretaceous and Jurassic are sandstone, while all those of the Palaeozoic are carbonate rocks such as red limestone or dolomite (bioherms). Shows of oil and gas have been encountered also in the Cambrian and Triassic sediments.The broad structural features of this vast expanse of sedimentary rocks are the Moose Jaw syncline, the Sweet Grass-Battle River arch, the Alberta syncline, the Foothills belt, the Rocky and Mackenzie mountains, the Great Bear-Slave Lake basin, and the Mackenzie Delta Basin area.This contribution outlines the .stratigraphy and structure of the Basin area, and gives examples of present producing oilfield structures and stratigraphic traps.Part 1.-Regional StratigraphyIntroductionThe vast expanse of relatively undisturbed sedimentary rocks of western Canada has long been recognized as prospective territory to search for oil and/ or gas. This search in western Canada dates back before the turn of the century, but, considering the size of area to be explored and tested, the effort an<l money expended upon it, which, before the recent discovery of oil at Leduc, Alberta, appeared large and fruitless, now seems almost ridiculously small. A check-up of effort and money expended prior to and since the Leduc discovery would undoubtedly reveal that more wildcatting and development has taken place during the last two and a half years than during all previous years combined. The figures would astound not only the average citizen, but many within the industry itself."

Jan 1, 1950

By Julian Boldy

"A review of lI5 significant volcanogenic massive sulphide discoveries in the Canadian Precambrian during the past 65 years reveals that only 7% resulted from surface exploration methods aimed at depths below the effective reach of current geotechnical systems. This has been due to the relative ease of shallow discovery, resulting in the harvesting of ore deposits within 100 m of surface. This surficial layer has been more or less effectively supersaturated by routine exploration. In view of the fact that a mining district&apos;s metal content is not likely to be confined to a surficial layer, the time has come to explore the vertical dimension, prospecting for ore at depths in excess of 150 m in productive districts.Essential to this task is an understanding of the Precambrian volcanogenic ore deposit model. The deposits generally have .a tendency to be associated with the terminal phases of felsic volcanism, and to be located along certain time-stratigraphic horizons, marked by the products of volcanic exhalation. The significant massive sulphide deposits are discrete entities, ranging from the top 5% of deposits greater than 45 million tonnes in size, with a surface area of 0.30 km2, to median-sized deposits greater than 1.2 million tonnes in size with a surface area of 0.02 km2. These significant economic ore deposits range in value from $5.5 billion for the top 5% of deposits to $125 million for median-sized deposits. In terms of their frequency of occurrence, the former group has a 4% distribution and the median-sized deposits have a 15% distribution.An historical review of many of the principal Precambrian mining districts, such as Noranda and Flin Flon, shows that major tonnages are usually discovered during the initial phase of application of each new geotechnical search system, until carried to its ultimate limit of effective depth penetration. With the exception of the Noranda district, the mean depth of ore discovery in the other districts is still generally confined to within 50 m of surface.Targeting deep ore is difficult. One effective prospecting method is the detection of fracture-controlled mercury leakage haloes in outcrop (or core) above and peripheral to blind deposits. This technique has proved to be a useful pathfinder, and focuses attention on deposits buried at depths in excess of 700 m in some instances. Down-hole EM systems also promise to be effective in locating deposits previously bypassed by drilling. In addition, trend surface analysis programs of trace element geochemistry should be used as an aid to targeting ore by directing exploratory drilling along the plane of ore-hosting stratigraphy.By definition, mining districts have a proven ""favourability"" for the occurrence of ore. Discovery probabilities in these districts will be considerably enhanced if future search efforts are concentrated below a depth of 150 m, and more use is made of ""deep"" ore search systems coupled with sound geological reasoning. Deep drilling programs to a depth of800 m should initially be designed to search for the top 25% of deposits greater than 3.3 million tonnes in size, with a surface area of0.05 kmt. :a value of$310 million and a 12% frequency of occurrence; This can be accomplished for an over-all cost approximating $40,000 per drill hole. If the search depth is limited to 400 m, the over-all cost of each drill hole is $20,000, equivalent to expenditures routinely allocated to grassroots exploration drilling in the remote greenstone belts of the Precambrian. Depending on a company&apos;s objective, prospecting for deep ore offers a stimulating challange - though risky, it has its rewards."

Jan 1, 1981

Purpose of TSUG Continuous Improvement in Mining Share Best Practises Exchange Ideas Network for Frontline Supervisors and Middle Management Meetings ? Two per Year -Spring and Fall ? Thirty Five to Forty Attendees ? Rotate Between Host Properties ? Host Mine Provides ? Meeting Room for One Day Tour of Mine and Maintenance facilities on Second Day

May 1, 2010

By Arthur. H. Winckers, Stephan L. Chryssoulis

"The deportment of gold in residue samples of cyanide leach tests of David Bell ore from level 6A block 13 was established using a comprehensive quantitative mineralogical approach. In every test the feed was first pre-aerated for 4 hours, followed by 48h cyanidation. Test no. 2 was done without lead nitrate and yielded a residue assaying 3.03g Au/t. In test nos. 4 and 9 lead nitrate was added before pre-aeration at 0.03kg/t and 0.3kg/t respectively yielding residues of 1.04 and 0.81 g Au/t.The mineralogical approach employed to establish the deportment of gold involved superpanning, to preconcentrate the free gold and assaying of the tailing fraction to determine the gold associated with quartz. It was thus determined that without lead nitrate added 47.2% of the lost gold is in the form of residual free gold particles less than 20 µm in size. It is this form of gold which is under represented in the residues of leach tests with lead nitrate added.Having eliminated coarseness of gold particles as a factor for lower recovery, it was determined that the residual gold particles have extensively contaminated surfaces. Amongst the deleterious surface contaminants identified: S, As, Ag, Sb and Hg, the two most harmful are S and Hg because of their concentration on the surface and rate of accumulation.Mercury and Ag are minor constituents of native gold at David Bell (average composition Au: 78.9 wt%, Hg: 18.5 wt% and Ag: 2.6 wt%) and they become enriched on the surface of residual gold particles because of their slower rate of dissolution in cyanide. The other elements absorb onto the gold particles from solution.The beneficial effect of lead nitrate was documented by comparative surface analysis of gold from residue samples of 48 hour leach testing with and without lead nitrate added and from time dependent (0-2 hour) leach tests in the presence and absence of lead nitrate. Lead nitrate accelerates the dissolution of gold by performing the following functions: (i) catalytic effect on the cyanidation of gold by accepting electrons; (ii) reaction with surface sulphur to form PbS which is then removed by oxidation; (iii) catalytic reaction on amalgam and Ag facilitating the cyanidation of Hg and Ag thus slowing down their build up onto the dissolving gold particles and (iv) the precipitation of sulphide sulphur from solution thus minimizing its build up on the surface of dissolving gold particles which is believed to facilitate the access of cyanide ions."

Jan 1, 1996

By W. Keith Buck

Introduction During World War II years, the magnetometer was used by various field parties of the Geological Survey of Canada, specifically in the search for chromite, a strategic war mineral. Throughout the summer of 1944, Professor J. W. Ambrose used the instrument experimentally on eight separate projects (1). Since then, several members of the Survey have come to consider its use to be of valuable assistance in the season&apos;s mapping. Dr. C. H. Stockwell, in particular, regards use of the magnetometer as a necessary part of detailed geological survey work. Throughout the field season of 1949, the magnetometer was used by Dr. Stockwell?s party as an aid to mapping in detail, to the scale one thousand feet to the inch, the south-west quarter of Dasserat township, Temiskaming county, Quebec. The principal geophysical project that was undertaken was the location of the Horne Creek fault and the Diabase fault in the area approximately midway between Arntfield and Kearns, on the Quebec side of the Interprovincial border. The location of these faults on either side of this central area was known. The Horne Creek fault is a subsidiary fault to the Cadillac &apos;break&apos; which extends ?westward from Val d&apos;Or through Cadillac to beyond Larder Lake. It lies to the north of that major fault zone and has a general southwesterly trend.

Jan 1, 1951

By Schrade F. Radtke

THE law of our present industrial society is the law of the jungle. By this I mean survival of the fittest. I do not refer to man or animal or the development of superior genetic strain. Rather do I refer to one's product, one's process, or one's material of construction. Each must perform in a superior manner or it is doomed to extinction; it must be steadily improved so that it can meet the competition of ether materials, of other equipment, or other processes. We have before us the classic examples of the horse and buggy vs the automo-bile, cf silk vs nylon, of the steam locomotive vs the diesel engine; in each case, a superior product has virtually wiped out its predecessor. Furthermore, a product, process, or piece of equipment is sold on its performance, together with engineering data which define its •characteristics and performance. For the most part, the present day sales-man must deal in terms of engineering performance of his product; he must know competitive materials -their strength and limitations as well N either old fashioned salesmanship, tradition, nor custom could have saved the horse and buggy from extinction; a superior product which has been steadily and con-sistently improved won out, 'and in turn, this change-over caused a dramatic• change in our whole way of life.

Jan 1, 1960

By A. Paulin, J. Roth, S. Spaic

This experiment was carried out to see whether copper-iron ingots from Late Bronze Age hoards could have been produced by smelting ferruginous copper ores. Since ferruginous copper-ores are chalcopyritic, chalcopyritic concentrate from a present day copper mine was dead roasted in our experiment in lieu of a rich chalcopyritic ore. Charcoal was used as a reducing agent in the reduction of calcine (i.e., a product of dead-roasting), and quartz sand was used as a flux. Two separate metallic solutions, a copper-base and an iron-base alloy, were obtained as a result of two factors: the presence of carbon and the miscibility gap in the Cu-Fe-C system. The metallic melts appeared in a form of bigger or smaller droplets, enclosed by a molten slag which, during the cooling, solidified into metallic beads. The presence of both metals was noticed in the majority of the examined beads. It was therefore concluded that calcine consisted of an intimate mixture of oxides of both metals which were simultaneously reduced during the reduction process. Due to the miscibility gap in the Cu-Fe-C system, separate iron and copper regions were formed in the beads. In both regions, sulphide inclusions were found. The formed molten copper and molten iron solution were found to be saturated solutions. The metallographic analysis revealed the precipitation of iron out of copper and that of copper out of iron during the cooling and solidification of melts. The formed slag contained little iron and no copper oxide.

Jan 1, 2001

By T. Senga, T. Namihira, S. Terada, S. Owada

"Electrical disintegration (ED) has been well known as a good comminution method to improve liberation of compositional phases because it was reported that electron avalanche could occur preferentially at phase boundary. But the detailed mechanism of the ED has been still not known. This paper describes the results of ED experiments using synthetic binary sample, copper/resin, under the conditions of various distance between electrodes, and discusses the energy distribution in the three kinds of phenomena in the ED process, which are(1) streamer progression in water, (2) electron avalanche in water, and (3) electron avalanche in solid sample, by measuring current and voltage with elapsed time. Then, it has been found that the energy distribution in the phenomenon (1) is quite low and that the distribution in the phenomenon(2) had a considerably large compared with that in the(3), which indicates that the shockwave generated in water could contribute much to the sample breakage.INTRODUCTIONElectrical disintegration (ED) has been well known as a specific comminution technology which enhanced selective breakage at phase boundary and lead to a good liberation among compositional phases1-6),but the detailed mechanism has not been clarified yet. This study describes energy distribution among the phenomena in the ED process by using a synthetic binary sample, copper/resin, the phenomena of which are (1) streamer progression in water, (2) electron avalanche and shockwave generation in water and (3) electron avalanche in solid sample usually at phase boundary. The energy distribution could be calculated from ED experiments and from voltage-current changes between electrodes as a function of elapsed time.SAMPLE AND EXPERIMENTALSampleThe sample used in this paper was a synthetic binary solid of copper/resin as shown in Figure1.Cut and polished pure copper lump was put into silicone mold and melted epoxy resin was poured into it and cooled, then, finally the binary sample was polished and molded in the form of 10 mm * 10 mm * 10 mm."

Jan 1, 2017

Electric Vehicle Controllers Ltd. ?EVC started in 1981 ?Underground electric locomotive drive systems ?Developed tandem load sharing system and radio ELOS controls ?Locomotive autonomy systems ?Entered space technology development in 1999 with NORCAT to develop Mars drill for CSA ?Commercial distributor for drilling systems, lunar physical simulants, electric mobility systems and lunar mining technologies

May 1, 2009

By P. H. Tolcher

Canada, as the Free World's largest mine producer of zinc and the third largest mine producer of lead, has a vital interest in the future growth in demand for these metals. This paper traces the development of lead and zinc consumption in the last two decades, both on a total-Free-World basis and by major market areas. How Canada, as a major mine producer, has shared in this growth is also indicated. In addition, future consumption for both metals in the current decade of the 1970's is fore-cast. The demand these projections will make on Free World mines, particularly on Canadian mines, is examined. Some of the opportunities and challenges the Canadian mining industry will likely face during this period are also dealt with.

Jan 1, 1971

By J. C. Gilbert

"IntroductionTHE PURPOSE of this paper is to discuss in a general way the heavy oil situation in Western Canada, and particularly to acquaint those in the oil industry who have not participated in the heavy oil end of the business with past and current developments. The author has covered •briefly the location of the heavy •and asphalt-base oil fields, their geology, current drilling and production practice, the location of the •refineries capable of handling heavy crude, their products and markets, and the problems and future prospects of the industry.Location and Description of FieldsThe term heavy oil is generally used to denote crude of 20.9° gravity and under. Since the products from heavy oil are also to a lesser extent obtained from asphalt-base crudes of higher gravity, some mention will be made here of the latter; but in general the emphasis of the paper is on heavy oil as such.In the order of their production to date, the heavy oil fields and those light oil fields which produce asphalt-base crudes are : Lloydminster, Taber, Vermilion, Conrad, Princess, and Wainwright.The Lloydminster oil field has not only produced most of the heavy oil, but also is currently the largest producer, supplying at the present time about 80 per cent of the heavy and asphalt-base crudes produced in Western Canada."

Jan 1, 1952

By Pierre Sauvé, Alex Makila

"The Camflo stock of porphyritic quartz syenite is an irregular pipe-like body 200 metres in diameter injected along the axial plane of an E-W trending F2 fold, near the contact between the. Kewagama and Malartic groups. The stock plunges 55° to the NE, almost parallel to the fold axis. The stock, exhibiting pervasive, weak cataclasis with numerous, locally auriferous quartz veinlets, is cut by minor faults striking WNW and dipping about 45°NE.Two types of gold ore are distinguished at Camflo: ""porphyry"" ore and ""fault zone"" ore. ""Porphyry"" ore, accounting for 90% of the gold produced, forms wide zones within the stock. The zones are irregular in shape but tend to be oriented E-W in plan view (on a horizontal plane) and are elongated paraliel to the plunge of the stock. These zones are more abundant in the northern part of the stock. Differences between ore and barren porphyry are not obvious. ""Fault zone"" ore occurs outside the stock along minor faults, particularly in differentiated sills offer rodiorite and felsic granophyre. Gold grade is roughly proportional to the pyrite content which in turns depends in part on the original magnetite content of the host rock. Although both types of ore show some correlation between Au and S, the Au/S ratio is considerably higher in porphyry ore.The bulk of the gold is in quartz syenite and in felsic granophyre, the most brittle lithologies at the mine. Presumably, the vertically continuous, pipe-like stock, made up of shattered rock, provided the main channelway for the ascending mineralizing solutions."

Jan 1, 1990

By D. Campbell Mackenzie

THIS paper is submitted primarily to put on record the results of a number of experiments carried out at the Wingdam mine of Consolidated Gold Alluvials of B.C., Ltd., with the object of establishing a reliable method of concentration of &apos;wash&apos; and a maximum recovery of gold from the concentrate. It will be generally admitted that, during the last two decades, a tremendous amount of research work has been carried out, both by private companies and Government departments, with a view to improving the technique of the recovery of gold .from quartz veins or lodes. So thorough have been these investigations that milling practice at a modern quartz gold mine is almost an exact science, carried out with meticulous accuracy. In placer mining, on the other hand, very little departure from old traditional methods can be noted, with the exception perhaps of the more modern gold dredges. This may be due to the fact that the concentration of placer gravels, up to a certain point, is comparatively easy. Only a simple equipment of sluice box and riffies seems necessary where the gold is coarse and the gravel free from clay. In the early days of placer mining, when claims were rich and fairly 5hallow, nobody worried very much about fine gold; and, if clay was present, an enlarged dump box was constructed in which the gravel was subjected to a rather desultory puddling. That large quantities of gold are lost in normal placer practice is generally admitted. Some 26 years ago, I had inspectorial charge of many bucket dredges on the Ovens river, in Australia. Occasionally it was necessary for a dredge to work through its own tailing to reach a new section, and almost without exception enough gold was recovered from these tailings to defray the total cost of moving the dredge. Since those days, the technique of gold recovery in dredging has been considerably improved and it is still receiving close attention. Outside of dredge mining, most placer operations, deep or otherwise, are as they were-notorious gold losers, paying little attention to the recovery of fine gold and taking an absurd amount of time over each clean-up. In the Cariboo district of British Columbia, the alluvial gold is usual y associated with varying quantities of black sand (magnetic) and grey sand (non-magnetic); and it can be taken as axiomatic that, if you save all the black sand and grey sand, you save practically all the gold. It is on this hypothesis that we have carried out our research work and brought our recovery system up to its present highly satisfactory standard.

Jan 1, 1937

By G. Hamel

The LCL&L process (Low Caustic Leaching & Liming) is a patented hydrometallurgical route developed by Rio Tinto Alcan (RTA) to economically process spent pot lining (SPL) generated by aluminum cells. The three resulting end-products (carbonaceous, fluorinated and caustic liquor) are inert and have valorization possibilities. An industrial size pilot plant located in Saguenay (Quebec) was inaugurated in mid-2008 to demonstrate and optimize the technology. This paper describes characteristics of the LCL&L process and the experience acquired by RTA since the plant&apos;s start-up, including ramp-up capacity and technology challenges that were overcome. Possible end-products valorization methods are also presented. The carbonaceous end-product can be separated into carbon and brick rich fractions and used as either alternative fuel, reducing agents, or as raw material for third party processes. The development of a conversion process for the fluorinated end-product would allow its reuse as a substitute to fluorspar mineral for aluminum fluoride production. Finally concentrated caustic liquor is already valorized at the nearby RTA Vaudreuil alumina refinery.

Jan 1, 2011

By R. J. T. Charles

Introduction An apparatus that will measure the surface area of a few of the simple minerals with a high degree of accuracy has been described by J. W. Bell (1). His apparatus consisted essentially of a photometric device that would measure the turbidity of fine particle suspensions. Turbidity, in this case, was considered as a function of surface area. Bell&apos;s method of surface area determination seemed to offer possibilities of extension and improvement to the point where it might approach a general method of particle size measurement. Theoretical and Practical Considerations of the Photometric Method In order to illustrate how turbidity may be considered as a function of average particle size, and to indicate the type of results expected from a photometric method of particle size measurement involving turbidity, the following theory may be hypothecated. If a number of particles, considered as spheres of uniform diameter, are placed at random in the path of a beam of light, the following expression, which will give the change in light intensity as a function of the diameter of the particles, the specific gravity of the material, and the weight involved, can be formulated from the Beer-Lambert Law:

Jan 1, 1951

By C. Gerow

THIS paper is entitled "Some" problems, rather than "The" problems, met in selling coal, since the problems to be met in selling any commodity have to deal with an infinite number of circumstances and conditions. These are believed to be more varied in the case of coal than probably any other commodity. This is due, perhaps, to the fact that coal has been one of the basic materials in the guiding of industrial and national achievement for the past two hundred years. During this time its use has developed from a most haphazard one to uses involving all modern scientific methods, which, rather than simplifying matters as regards the marketing of coal, have added many fresh problems, and these vary according to the particular market served. Since the concern of this paper is primarily the selling of Nova Scotia coal, it is proposed to deal chiefly with some of the specific conditions met in the markets presently served by this coal. For the purpose of discussion, these markets may be considered as divided into three main groups, namely, the Maritime market, the Quebec market, and the Ontario market. THE MARITIME MARKET First of all, let us consider the Maritime market. This is a market which has been regularly served by Nova Scotia coal since coal mining became the first industry in Cape Breton, slightly over one hundred years ago. Conditions as applying to the use of coal have naturally tended to adjust themselves to the characteristics of the coal most readily available, and, therefore, marketing problems are fewer in the Maritimes than in districts where many coals of varied characteristics are offered. Up to recent years, the problems involved were chiefly those of providing satisfactory service insofar as de-liveries were concerned. However, with the speeding-up of manufacturing processes and the necessity of reducing costs to a minimum, users of coal have become interested in obtaining coal that will give the most economical service. It is, therefore, now of importance that the salesman should have full knowledge of the particular conditions applicable to each customer&apos;s use in order to deal to the best advantage.

Jan 1, 1936

Presentation Outline ERM ? corporate profile Background to sustainability reporting GRI G3 Guidelines (Oct 2006) Best practice examples Contact information ERM ? corporate profile Over 35 years of experience World?s largest all-environmental consultancy* 130+ offices in 40+ countries; 3,200+ professional staff Worked with >50% of the Global Fortune 500 (FY07) Annual turnover > US$500 M (FY07) 2008 Environmental Advisor of Year** Offices/Staff ? Canada (5/50) and US (65/1,350) *Source: Engineering News Record: July 2, 2007 ** Source: Acquisitions Monthly: December 2007

May 1, 2008

By Dallas Bienhoff

Boeing Study Team Participants Andrew Daga & Associates American Aerospace Advisors Hamilton Sundstrand Harris Honeywell ILC Dover Lunar Transportation Systems Oceaneering Orion Propulsion SICSA Thin Red Line USA LSSCA BAA Topic 2: MFHE Definition Minimum Functionality Habitation Element Deployable Habitat DHE Update The Path to Growth

May 1, 2013

By N. Birbilis, S. Kairy, C. R. Hutchinson, D. Jiang, D. R. Feenstra, O. Gharbi

"Recent developments in metal-based additive manufacturing (AM) technology have generated considerable interest in multiple industries, owing to flexibility in design and the ability to produce final components in their net shape. The AM of high-strength aluminium alloys has not been widely explored, due to findings of undesirable microstructures leading to short fatigue life and poor fracture toughness; restricting the application of AM to lower strength aluminium alloys (with cast-like Al-alloy compositions) to date. Herein, aluminium alloy AA2024 (Al-3.6Cu-1.2Mg) was additively manufactured via selective laser melting (SLM), with the resultant microstructures and corrosion properties characterised and compared to wrought AA2024-T3. Microstructural characterisation was carried out using transmission electron microscopy (TEM), revealing SLM produced AA2024 included a population of ?-phase (Al2Cu) in preference to S-phase (Al2CuMg) typical of wrought AA2024. Additionally, the corrosion properties were investigated by potentiodynamic polarisation in a range of NaCl concentrations, whilst elemental corrosion rates were also determined (including for open circuit exposure conditions) and quantified in situ with an inductively coupled plasma mass spectrometer coupled with an electrochemical flow cell. Results revealed a significant improvement in the corrosion resistance, and elemental dissolution of AM prepared 2024 relative to wrought AA2024-T3.INTRODUCTION Aluminium alloys remain the preferred candidate materials in applications requiring a balance of low density and strength. The ability to produce net shape components from aluminium alloys has accelerated due to recent developments in metal-based additive manufacturing (AM) technology, including selective laser melting (SLM) and powder bed 3D printing. The AM of Al-alloys, including Al-Si-Mg (namely AlSi10Mg), has become widespread commercially in recent years. Alloys including AlSi10Mg offer reliable and reproducible production by AM, however such alloys (and variants thereof) are not high strength alloys. The pursuit of higher strength AM Al-alloys presents significant merit to multiple industries; however, such higher strength AM Al-alloys have not been widely studied to date. The solidification of high strength Al-alloys during conventional (casting) operations needs to be executed in a manner that avoids so-called =hot-tearing‘, which can arise as a result of the solute type and loading. A report on the solidification of a high strength Al-alloy prepared by AM, along with factors related to solidification, was recently covered by Pollock and co-workers (Martin et al., 2017). It was reported that AM of high-strength aluminium alloys (which have to date been principally based on the compositions of wrought high strength Al-alloys) may lead to undesirable microstructures that reduce fatigue life and result in poor fracture toughness; presently limiting the application of AM to lower strength aluminium alloys (with cast-like Al-alloy compositions) to date."

Jan 1, 2018