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By K. Scalise, M. Teixeira, K. C. Kocsis, J. Parrish

"This paper aims to introduce and discuss a newly developed algorithm, which can be uploaded on smart watches and other mobile devices to inform and protect underground personnel working in hot and humid environments. Using this algorithm, the metabolic rate (M) of a worker can be determined in “real-time”. In addition, besides warning signs and alarm signals emitted by the smart watch, the algorithm has the ability to determine work-rest time periods based on the worker’s physiological parameters (e.g. age, height, weight, gender) and the climatic parameters (Td, Tw, flow velocity). This paper also investigates whether a re-designed auxiliary ventilation system can provide appropriate work conditions in the production stopes. INTRODUCTION An underground environment with high temperature and humidity conditions generated from various heat and moisture sources can significantly affect the thermoregulation processes of the human body. This can lead to heat-related illnesses such as heat rash, heat cramps, heat exhaustion, and heat stroke. Heat stroke is a serious illness that carries a high risk of fatality, if the underground workers are not immediately treated and the climatic conditions are not corrected (McPherson, 1993). There are two methods used to control the climatic conditions in underground mines: (1) Using ventilation and cooling systems to reduce the thermal stress on the mine workers, and (2) Reducing the heat transferred to the ventilating air from major sources such as: strata, auto-compression, mining equipment, groundwater, blasting, etc. The heat from strata and auto-compression is transferred to the ventilating air at varying degrees, based on factors such as the virgin rock temperature (VRT), the thermal properties of the surrounding rock formations, and the surface air temperature. However, the use of mining equipment and blasting processes can be managed to reduce their contribution to the mines’ overall heat load. To provide appropriate work conditions, selecting the most suitable cooling method depends on the level of heat to be removed, the location of the problem areas, and economic constraints (Brake & Bates, 2002; McPherson, 1993). Because every mine is unique, it is essential to monitor the climatic conditions to select the most appropriate method of cooling. A majority of the time, simply adjusting or re-designing the auxiliary ventilation system can efficiently remove the heat and dilute the contaminants. This may involve moving the ducting system, changing the size of the duct, changing the size of the auxiliary fan, or switching from forcing to an exhausting fan arrangement. If the required air volumes are higher than the existing primary ventilation system can supply, other measures may need to be taken to increase the airflow delivery. This may include regulating the flow in some areas of the mine to increase airflow to the desired area, adding booster fans, or replacing the primary fans."

Jan 1, 2019

By I. Westermann, K. Marthinsen, M. S. Remøe

"Al-Mg-Si alloys often add small additions of e.g. Mn or Cr, to form dispersoids, which may act as nucleation sites for Mg2Si particles after homogenization. The purpose is to ensure a high density of uniformly distributed small ?’-particles, which can be dissolved during further processing prior to the final age hardening step. However, their density and spatial distribution are critically dependent on the homogenization procedure. It is therefore important to have a robust and reliable method for assessing their spatial distribution. In the present work an existing methodology for assessing spatial uniformity, the Global Shannon Entropy (GSE), has been implemented and evaluated for different dispersoid structures characterized by scanning electron microscopy. This metric is highly dependent on the parameters used, but by careful selection of adequate parameters, it can be effective in detecting non-uniformity. An important weakness with the GSE was identified, and a modification to improve on the ability to differentiate degrees of non-uniformity is suggested. To evaluate the proposed methodology, the effect of heating rate on dispersoid precipitation behaviour during homogenisation of four Al-Mg-Si alloys with different Mn/Cr-content has been investigated. The metric with the new term has demonstrated promising results, and improved the ability to differentiate degrees of spatial uniformity.INTRODUCTION Al-Mg-Si series alloys are the most common aluminium extrusion alloys and are attractive for applications in a range of sectors (e.g. construction, automotive and recently also in consumer electronics), due to their generally good combination of strength, ductility and corrosion resistance. However, their extrudability and end properties depend critically on the alloy chemistry as well as prior processing conditions. Coarse ß-AlFeSi or Mg2Si-particles typically have a detrimental effect on extrudability, while small dispersoid particles may affect recrystallization, grain growth and precipitation of Mg and Si. The strengthening potential in the final age hardening step depends strongly on the amount of Mg and Si in solid solution after extrusion. The manner in which these particles are spatially distributed will decide whether the final product will exhibit uniform properties, and the number density and sizes will determine the extent of the effect. As such, these are important characteristics."

Jan 1, 2018

This work illustrates the potential of two welding processes for joining AA1100-16 vol.% B4C metal matrix composite: laser welding process using a 4 kW Nd:YAG laser and Friction Stir Welding. A comparison is made between these two welding techniques in terms of microstructure and mechanical properties of welded joints. A large amount of brittle needle-like phases, together with some residues of B4C particles were observed in the fusion zone of laser welded joints. The use of Ti filler can improve the microstructure and increase the joint efficiency from 63% to 75%. On the other hand, the friction stir welding process being a solid state welding technique is interesting as it avoids the formation of brittle intermetallic phases. In addition, the breakage of B4C particles and the grain refinement of the matrix were observed in the weld zone. Consequently, FSW joints show much better mechanical properties than laser welded joints. Up to 100% joint efficiency can be achieved by FSW for annealed AA1100-16 vol.% B4C materials.

Jan 1, 2011

By C. H. Stockwell

RICE LAKE-BERESFORD LAKE area, situated 100 miles northeast of Winnipeg (Figure 1), is Manitoba's foremost gold mining district, although it is exceeded in gold production in the Province by the Flin Flon base-metal mining district. At present, the area is producing at the rate of about one and three-quarter million dollars annually, almost entirely from the San Antonio and Gunnar mines. The total production to date is about $14,000,000. Of this total, over $7,000,000 has come from the San Antonio mine, over $2,000,000 from the Gunnar mine, about $4,000,000 from the Central Manitoba mine, and the balance from several smaller properties. The writer has led Geological Survey parties in the area for the past four summers. The present paper gives a summary of the results of this work and also includes the findings of C. S. Lord, who was in charge of a party for one year. Much valuable information was obtained from earlier published reports on the area and from officials of mining companies, to whom the writer is indebted for their kindly co-operation. It is impossible in this short paper to give proper credit to the earlier workers or to discuss certain points o disagreement between their conclusions and those presented here. For further information the following references may be consulted.

Jan 1, 1940

By Lizelle Glaner

An investigation was carried out by Mintek to investigate the influence of additions of gold to ?Fecraloy?, alloys based on Fe-Cr-Al. The aim was to try and improve the oxidation resistance of the ?Fecraloy? alloys at elevated temperatures over extended periods of time. The ?Fecraloy? alloys are very oxidation resistant alloys already employed in industry as substrates for metallic catalysts in auto-catalyst systems for high performance cars. Since their life and durability is limited by the slow, but steady, oxidation of the substrates, any change in the growth or stability of the oxides could be an improvement.

Oct 1, 2003

By Richard Simon

This paper presents an ongoing study on the use of borehole breakouts to estimate in situ stresses at depth in a Canadian underground mine. Breakouts were identified using an acoustic televiewer (ATV) probe. Rock samples were tested in a laboratory to determine their failure curve. Breakout analyses were performed using a 2D failure criterion and a multiaxial failure criterion. Analyses were carried out using both short-term (peak) and long-term strengths (the latter considered here as being represented by the damage initiation threshold DIT). The analyses have shown that the use of the longterm strength and a multiaxial failure criterion leads to results that are more consistent with stress measurements performed in the field, in the vicinity of the mine.

Jun 1, 2012

By Emmanuel Henry

Hanging wall deformation monitoring at the Kiruna Mine is a major concern for Luossavaara- Kiirunavaara AB (LKAB) since underground production is deepening towards the Kiruna Town. In the quest for more effective monitoring techniques, LKAB decided to evaluate satellite-borne Synthetic Aperture Radar (SAR) interferometry?s ability to monitor ground subsidence by generating continuous deformation maps from satellite radar images. While adopted by other geoscience-related industries, SAR interferometry is still relatively untested in the Mining industry. This paper describes how subsidence is actually monitored on the Kiruna Mine?s hanging wall and gives an insight on SAR interferometry?s principle. The encouraging results are discussed as well as the technique?s benefits (continuous deformation mapping, low cost, fast, etc) and limitations (sensitivity to snow and vegetation cover).

May 1, 2003

By John H. Walsh

"ForewordThis paper is to be published in two parts in succeeding issues of the CIM Bulletin. In Part I, the problem of global climate change is explored together with a summary of the government's present policy in this field. Implications for the steel industry are examined as are possible strategic responses. Part II of the paper will present a new possibility - the joint production of iron and liquid fuels useful for transportation purposes. In the joint production case, the objective is to use carbon for more than one purpose in what might be termed a 'carbon cascading' technique. ABSTRACTIt is becoming increasingly probable that emissions of carbon dioxide from the fossil fuels will have to be reduced to deal with the threat of global warming. This issue is likely to be resolved one way or the other in the period 1995 to 2000 which does not leave much time to develop responsive options. In the intervening period, the policy of the Government of Canada is to stabilize emissions of greenhouse gases at their 1990 level by 2000, by encouraging greater efficiency in the use of energy. Should further reductions prove necessary, economic instruments would probably be employed but these would not be applied before a comprehensive international agreement is reached.There are three main themes in this paper: it is assumed that measures to control carbon dioxide emissions will in fact be necessary by the tum of the century; that there will be a rising need for liquid fuels to supply the world's steadily growing fleet of motor vehicles for many years to come, and that the future niche for Canada 's industry in such a carbon-constrained world will be the operation of the energy-intensive industries with efficiency and environmental sensitivity.The steel industry, as a large user of both coal and energy in other forms, would be significantly affected by a need to reduce carbon dioxide emissions. This paper first examines what might be called the conventional responses open to the industry in such a situation and then explores a new possibility for making better use of carbon by the co-production of iron and liquid fuels."

Jan 1, 1992

By A. J. McLaren

Introduction Gold holds an important place among the mineral products of Manitoba. In value, it ranks second only to copper, which in 1931 attained first place. The gold production increased from 23,189 fine ounces in 1930 to 102,969fine ounces in 1931. The production for 1930, worth $479,359, came almost entirely from the Central Manitoba mine. The production for 1931 was worth $2,128,558, of which $1,509,018 came from the Flin Flon mine, $528,951 from the Central Manitoba, and $83,497 from the Sherritt Gordon. The Gem Lake mine and some prospects produced $7,785. The total output of gold in Manitoba, from the first recorded production in 1917 to the end of 1931, is estimated at 178,669 fine ounces, valued at $3,693,332. The production for 1932 promises to reach a new high record, due chiefly to the stepping-up of tonnage at the Flin Flon plants and the coming into production of the San Antonio mill in May. History The Manitoba Act, constituting Manitoba a Province of the Dominion, was passed in 1870 and provided for the vesting in the Crown of all un-granted or waste lands of Manitoba, as well as for the administration of these lands by the Dominion of Canada for the purposes of the Dominion "subject to, and except and so far as the same may be affected by, the conditions and stipulations contained in the agreement for the surrender of Rupert's Land by the Hudson's Bay Company to the Crown". Included in these waste lands were large areas later prospected and staked out as mineral lands. Up to the year 1912, that vast territory extending from the 12th base line to the 60th parallel of latitude, and from the Saskatchewan boundary to Hudson bay, was part of the District of Keewatin. Although added to Manitoba in 1912, the administration of its mineral lands also remained vested in the Dominion, so that all mineral lands within the Province upon which deposits of gold ore have been found were disposed of and administered by the Mineral Lands Division, Department of the Interior, until the transfer of the natural resources to the Province of Manitoba, on July 15th, 1930.

Jan 1, 1932

By Norman A. M Macleod

FOR the past seven years, all flotation at the Britannia mill has been done in Forrester Air-Lift cells. Prior to 1931, the roughing and part of the cleaning operation had been performed in four 21-cell and two 14-cell M.S. machines. The resulting economies in reagent, power, maintenance, and general operating costs, and the increased recovery, more than justified the exclusive use of the Forrester machine. About three years ago, the possibility of still further improving the efficiency of the flotation section was the subject of considerable discussion and experiment. Arising from these experiments, tests were made of the practicability of using a cell of greater depth than that of any pneumatic or mechanically-agitated machine in common use. Cells were constructed with depths of 7 .5 feet, 10 feet, and 15 feet, and, in all cases, a very definite improvement in operation was indicated. The cell now being used in the mill treats from 5,500 to 6,200 tons of dry feed per day. It is 100 ft. long by 5 ft. wide by 8 ft. deep, and has replaced a total length of over 500 feet of standard Forrester machine. The choice of a depth of 8 feet was governed by the type of blower which was available-in this case, a Roots-Connersville blower, driven by a synchronous motor and delivering 6,000 c.f.m. of free air at 4.0 pounds per square inch. At the Chelan Division of the Howe Sound Company, where a new mill was recently built, all flotation is carried on in cells 10 feet deep, with good results.

Jan 1, 1938

By M. Sahoo, P. Burke, Y. Fasoyinu, J. P. Thomson

The effects of grain refinement, mold temperature and chemical composition on the hot tearing resistance of aluminum alloys 535.0 and 206.0 has been studied by pouring constrained rod castings in metal molds. In addition, two prototype components that could be used in automotive applications were also poured from both alloys by gravity tilt-pour and low pressure permanent mold casting processes. This paper summarizes the results and issues encountered during the casting trials. It was shown that grain refinement and mold temperature ::::: 400°C reduced, and sometimes eliminated hot tear cracks in both alloys. The two prototype engineering components could be cast successfully from both alloys in metal molds. The metallurgical issues related to molten metal treatment and processing temperatures were well controlled. However, issues related to the control of hot tearing, casting and mold design must be addressed in future studies to guarantee the production of defect free castings.

Jan 1, 2006

By Yong Kang, Bingyuan Yan, Dandan Zheng, Xiaochuan Wang, Dengfeng Su, Dongyang Li

"According to the characteristics of rock mass and the directional cutting technology of water jet, a new idea of light shock controlled blasting with water jet slotting was put forward. Based on the fracture mechanics theory and the stress wave theory, the mechanism of damping with water jet slotting was analyzed. On the basis of the above, the evolution law of the pressure wave and displacement field during the blasting were simulated by FEM software ANSYS/LS-DYNA. The result shows that: the oriented slot plays a good role in orientation during the blasting, and makes the energy generated by gas released by the explosives gather at the tip of the oriented slot, which makes it easier for the main crack to expand along the oriented slot and indirectly reduce the stress effect on the protected object. Meanwhile, the energy of the seismic wave is reduced while transmitting through damping slot. Finally, compared with the normal blasting with damping ditch, the maximum acceleration is reduced by 15.62%, the maximum velocity is reduced by 52.99%, and the maximum displacement is reduced by 68.32%. INTRODUCTIONIn recent years, with increasing demand for energy and space, an increasing number of underground projects have been under construction. Drilling-blasting method, as a traditional main method for rock excavation, is still an indispensable means in the engineering construction. As is known, blasting vibration will cause the deformation and unstable of the existing building structures, so how to reduce the influence on the existing building structures caused by the blasting vibration has become the focus. Traditional shock absorption measures mainly include three kinds: the first one is pre-splitting blasting, the second measure is to change the parameter of explosive filling, and the last one is to excavate damping ditch between the protected object and blastholes. However, engineering practices show that: the protected rock may be damaged in the process of pre-splitting crack construction by blasting, the second measure is difficult in operating, and the third measure is troubled by large work quantity (Song Guangming, 1999; Lou Jianwu, 2004; Lou Jianwu, 2005; Li Xibing et al., 2008)."

Jan 1, 2015

By D. Mas Ivars, K. Suzuki, J. A. Vallejos

"A comprehensive geotechnical characterization has been undertaken at the El Teniente mine to describe and determine the rock mass behaviour strength properties of the primary copper ore. The Synthetic Rock Mass (SRM) modelling approach is used to simulate the mechanical behaviour of this heavily and unfractured rock mass. The micro-parameters of the model have been calibrated against mechanical properties and scaling laws for intact rock and veins, in order to represent virtual samples of four different geotechnical units. Results can be used to predict the rock mass scale effects, anisotropy, and brittleness properties that cannot be obtained using empirical methods.INTRODUCTIONThe primary copper ore at the El Teniente mine is described as very competent and massive, given that it exhibits a brittle behaviour (Rojas, Cavieres, Dunlop, & Gaete, 2000). This description is coherent with the geological description of the rock mass, which does not have discontinuities match as the definition provided by International Society of Rock Mechanics (ISRM, 1981). Only faults can be classified as discontinuities, but they are widely spaced. The primary copper ore has a high frequency of veins, where the cooper mineralization is hosted, these vein network structures are known as stockwork. Soft veins containing weak minerals as infill (chalcopyrite and anhydrite) control the disassembling of the rock mass during caving (Brzovic & Villaescusa, 2007).Presently, there are mainly two traditional methods used to estimate the strength of the rock mass: 1) determination of the strength envelope of the rock mass using scaling parameters from laboratory tests and 2) using numerical modelling based on back analysis of previous experiences of failure observed and measured in mining or civil excavations. The primary copper ore of El Teniente mine has no fractures; therefore, it is difficult to determine a rating that would enable to scale laboratory data, such as, RMR (Laubscher, 1977) or GSI (Hoek, 1994). This is the reason why the first option is not valid unless the entry data is manipulated or adjusted in order to obtain reasonable results. The second option requires, in general, a good characterization of a previous failure event in the rock mass, which is not always available. In recent years, new techniques of numerical modeling have been developed (PFC3D, ELFEN, Abaqus). Those methodologies are the third way to estimate the strength of the rock mass, but they are still in development. Particularly, the concept of SRM developed by Itasca is implemented in this study (Pierce, Mas Ivars, Cundall, & Potyondy, 2007; Mas Ivars et al., 2011), aiming to capture the real behaviour of the rock mass."

Jan 1, 2015

By J. A. C. Fortescue

"Reconnaissance geochemical mapping, based on the chemical analysis of waters, stream, and / or lake sediments had its origin in geochemical prospecting surveys carried out in New Brunswick during the 1950s. More recently, reconnaissance geochemical surveys carried out by government agencies for mineral resource appraisal purposes have been seen as a special case of regional geochemical mapping which is carried out with the aim of describing geochemical patterns f or elements which may he interpreted for mineral resource appraisal, environmental or geological purposes. The interpretation of pal/ ems on regional geochemical maps is based on the concepts of landscape geochemistry, in this paper, the regional approach 10 geochemical mapping is described with reference to an experimental regional geochemical survey which was completed in southwest Ontario during 1981-82. II is concluded, on the basis of data pal/ems for one element only (i.e. arsenic), that the new approach has much potential for solving modern problems in geoscience.""If things don 'I alter they will stay as they are... An old adage.IntroductionDuring the past hundred years topographic, geological, and geophysical maps have been made for all, or nearly all, of Ontario. During the past thirty years these maps have become related as components of what is now called geoscience. Geoscience maps at the regional (i .e. 1 :250,000) scale are often used together to solve general problems in earth science especially in relation to prospecting, or mineral re source appraisal."

Jan 1, 1986

By W. Swidzinski

"Zelazny Most" post-flotation copper mine tailings pond is the only place to of storeing wastes for KGHM POLSKA MI EDZ S.A. The flotation tailings is are the main waste stream in copper mining in Poland. Sufficient storage capacity for tailings is crucial for , thus uninterrupted production of copper is crucially related to the possibility of storing wastes in the pond. The pond covers a Its over 14 km2 arca, almost 50 m high dams making this dame this construction one of the largest in the world. The risk assessment of potential damage due to un stable ility loss of dams or environmental contamination, as well as safely constructing damsincrease of dams within the design criteriaprocess, require quick access to a large amount of the monitoring data , which in vast amount have to be monitored, that needs to be analyzed and processed and reported, every day. This In the paper describes the numerical information system "SyZeM" , used for designated to the "Zelazny Most" pond, baseding on the Oracle database and Geographical Information System , to manage the graphical and descriptive data in coherent way., is presented. The main structure of the system, as well as the methodology of storing, processing and reporting the geological, geotechnical, hydrogeological, geophysical, chemical and survey data are shown. The aspects of Optimizing optimal and risk mitigation and safe management of copper wastes and risk mitigation with the help of "SyZeM" are discussed.

Jan 1, 2007

By M. Alvarez-Silva, A. Uribe-Salas, J. A. Finch, M. Mimezami

The point of zero charge (PZC) of electrokinetically anisotropic minerals (chlorite and serpentine) was determined using the Mular-Roberts (M-R) titration technique, and compared to isoelectric point (IEP) obtained from electrophoretic mobility measurements. To validate the M-R technique, the point of zero charge and isoelectric point of two isotropic minerals (alumina and silica) were shown to be comparable. For serpentine and chlorite, respectively the PZC was found at pH 4.3 and 4.6, while the IEP occurred at pH 3.2 and <3. Settling tests showed that the maximum settling rate, which corresponds to aggregated particles, for chlorite was around pH 3, i.e., close to the IEP; lizardite did not show a conclusive maximum.

Jan 1, 2009

By H. Sano

Most of the dust generated from the copper smelting process in Chile has been stored after the stabilization by hydrometallurgical process because it contains high concentrations of arsenic. However, in recent years, the dust generation has increased because of degrading the quality of concentrate. In addition, the environmental regulations become stricter. On the other hand, valuable metals such as copper and zinc are contained in the dust at high concentrations and it is desirable to recover them. In this study, the effect of dust recirculation to the smelting process was examined in order not only to decrease the amount of dust but also to recover copper. Dust generation and the distribution of arsenic, lead, zinc etc. among the matte, slag and gas phases were evaluated as a function of the amount of recirculated dust, partial pressure of oxygen and temperature. It was found that the direct dust return to the smelting process was quite effective for the recovery of copper and the reduction of dust generation, but the acceptable dust amount was limited by the produced matte quality.

Jan 1, 2007

By M. H. ElMaghraby

This paper describes the development and validation of a strategy for vibration-based online detection of faults in a particular class of machinery commonly found in industry. This machinery is defined by two basic characteristics that preclude it from the application of standard online condition monitoring approaches. The first characteristic is that the machine is in a constant state of transient operation, thus making it difficult to differentiate between changes in transducer measurements that are due to variable duty and those that are due to machine malfunction or fault. The second characteristic is the fact that the machinery involves multiple sub systems that are subject to identical and simultaneous loading, operating environments and duty cycles. An example of such machinery is a system of multiple hydraulic pumps driving a common load. The monitoring strategy presented here employs an anomaly detection scheme together with methods of signal processing and feature extraction that exploit the parallel duty arrangements of this equipment. Preliminary data is collected from a pair or motor-gearbox assemblies used in a material haulage system in the mining industry. Testing and validation was performed on a mechatronic test bench with both healthy and faulted components. Experiments were carried out to investigate how various configurations of the system were able to detect different types of faults. The results indicate that this approach is effective and merits further investigation.

May 1, 2013

By A. C. de Araujo, M. G. Barbosa, R. Martino, S. Gaydardzhiev

The Iron Quadrangle district is a world-class iron ore mining district in the region of Belo Horizonte, capital of Minas Gerais state, in Brazil. Many mining companies have been mining high-grade hematite ores for decades throughout the region. The mines reserves often include itabirite ores which are available in high volumes, but have lower iron grades than hematite ores and require elaborated mineral processing to meet the requirements of downstream steelmaking. Itabirite ores have acquired importance, with the depletion of high-grade hematite reserves due to their intensive mining. The objective of this paper is to propose a geometallurgical model for the processing of itabirite ores from an Iron Quadrangle deposit, which will allow predicting the behaviour of ores throughout the deposit, according to their local variations. An initial step consists in characterizing representative samples of the different ores to acquire mineralogical and textural data. Then, itabirite ores of known characteristics are processed with different techniques, in order to extract the trends and key parameters upon which the geometallurgical model is developed. At first, the model takes into account the particle size distribution and its shift during mining and screening, as well as the chemistry and mineralogy of the material. Then, using the previously identified key parameters such as iron recovery, the model predicts the composition of the processing products. Finally, this data is used to model the mineralogy and mass recovery of the products. The geometallurgical model is of great importance, as it is able to model the processing of any sampled ore throughout the deposit. The incorporation of the results in a mining block model will assist mine planning and opens new opportunities for an optimized mining schedule.

Jan 1, 2016

By G. Morin, F. Chiesa, B. Tougas, B. Duchesne, Jocelyn Baril, N. Giguère

"An aluminum A356 compressor impeller was sand cast using the Low Pressure technique. The casting was limited in size (170 mm in diameter, 1.2 kg in weight) and very intricate in shape thus making 3D mold printing particularly favorable; indeed, producing this part by the traditional pattern-core box route would involve mounting 12 cores inside the mold while stringent dimensional tolerances are required as the impeller blades are only 2 mm thick. Consequently the molds were produce on the X-One MFlex printer of Quebec Metallurgy Center - CMQ. A dozen castings were produced with different casting temperatures and filling times so that it was possible to assess under which conditions complete filling of the mold cavity would be achieved. Filling and solidification modeling allowed predicting misruns and metallurgical properties inside the A356 (AlSi7Mg04) casting.INTRODUCTION Recent advancements in additive manufacturing enable foundries to produce molds without the tooling (pattern and core boxes) necessary when conventional technology is used (Eyad, 2016). This is particularly advantageous when dealing with intricate shapes and/or when a limited number of parts must be produced within a few days rather than in 5 weeks. An additional advantage is gained when producing prototypes (Johnson, 2016) as changes are much less costly and time consuming when made on a numerical 3D drawing rather than on patterns and core boxes. 3D printing is normally economical for a small number of parts; however, if the part is not too big and very intricate in shape such as the part that will be studied in the present work, 3D printing can be economical even for an important number of castings to be produced. On the other hand, low pressure casting is a high integrity casting process in which the mold cavity is filled from the bottom via a transfer tube in which the liquid aluminum rises under the pressure applied at the surface of the melt as illustrated in Figure 1. The filling can thus be precisely controlled, eliminating the turbulence created when the mold is filled from the top (gravity casting). Also, the pressure applied on the melt during solidification results in excellent feeding of the casting when conditions of directional solidification are met. In the present work, the compressor impeller shown in Figure 2 will be sand cast by low pressure."

Jan 1, 2018