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By Mohamad Sabsabi, André Hamel, André Moreau, Paul Bouchard

"Laser-Induced Breakdown Spectroscopy (LIBS) is an atomic spectroscopy technique used to measure elemental concentrations. It is well-adapted to in-situ and in-line measurements during materials processing in general, and pyrometallurgy in particular. It is an optical non-contact technique and it can measure nearly all elements, including light elements. Our group has developed a mobile prototype system to measure molten metals. The system includes a tube, also called a lance, one end of which is immersed in the molten metal. An inert gas flows in the tube and bubbles out below the surface. The LIBS measurement is made through the tube and onto the bubble’s surface. This is done to avoid measuring contaminants, slag, or fluxes often found at the surface of the melt. An added benefit is that the molten surface is constantly renewed and thus, more representative of the bulk. An alternative to using our lance is to use a tuyère, such as a gas injection tuyère in a converter, as we did several years ago in a nickel matte converter. In this presentation, we will show various applications emphasizing more recent developments. This includes the simultaneous measurement of the concentrations of Cu, Ni, Fe, Co and S in molten matte at 1125 °C. The more obvious industrial applications of the technology include determining the best time to end oxygen blowing in the converter and elemental concentration measurement during alloying.INTRODUCTIONThe mining industry continually faces challenges in optimizing cost and productivity. Because of the large volumes of materials that are being processed, small improvement can have a big impact on benefits. Better real-time information can help improve this optimization."

Jan 1, 2016

By F. P. Yungwirth

"IntroductionTrout Lake Mine is located about 5 km north of the Hudson Bay Mining and Smelting Co., Limited complex at Flin Flon, Manitoba. The mine was brought into production in 1982at the onset of a severe recession in the base metal market. The mine is operated as a joint venture with HBM&S, MMR and SMS.During the first several months of operation it became evident that there were opportunities to reduce costs at the mine significantly, and a productivity improvement subcommittee was formed to make recommendations. The first committee met in January, 1983 and consisted of the mine manager from Hudson Bay Mining, a geological expert and a maintenance expert from Outokumpu Oy, Finland, and a mine manager from Granges, Sweden.Recommendations from this committee were implemented during 1983 and a new subcommittee was constituted in 1984 to continue the work begun the previous year. The committee remains as constituted in 1984 and meets quarterly.The committee consists of M.A . Kirby , manager - Flin Flon Mines, HBM&S; Gustav Hoberstorfer of Mindelco , a Swedish mining consultant retained by Granges; Eero Laatio, mine superintendent of Keretti Mine at Outokumpu Oy in Finland; and Bob Bray, a mining consultant retained by Manitoba Mineral Resources.Many productivity improvements made in the operation are attributed to the work of this committee and other experts retained at various times throughout the mine life."

Jan 1, 1988

By F. W. Crossland

Losses of metal are often traced to incorrect pH/ORP signals in flotation, leaching, extraction, electrolysis, and precipitation processes, aggravated by pressure changes. IC Controls, a Canadian mining sensor manufacturer, developed a new superior pH/ORP sensor that stops metal losses, reduces environmental footprint and contributes to sustainability. The cause of incorrect pH/ORP signal is rooted in the reference. Reference junctions are designed to allow diffusion of reference chloride ions into the process but also allow process ions to diffuse into the reference. This development is important to mines and hydrometallurgists where sulphide, cyanide, ammonia and other poisoning ions are present in the process. These ions react with reference electrolyte components causing the signal to change, drifting from the correct process value. With fluctuating process pressure, ion in migration dilutes the electrolyte producing similar signal drifts. If process ion in-diffusion could be stopped, the pH/ORP signal would be accurate. IC Controls new pH/ORP sensor stops process ion in-diffusion, and remains accurate over long periods. New processes using higher pressure and fluctuating pressurized reactors will greatly benefit from stable pH readings. Similar to IC Controls' proven model 642 Mining pH sensor, our new model 647 contributes to sustainability through reducing disposal costs from waste reagents, lost metal and fewer used sensors.

Jan 1, 2014

By Nordau R. Goodman

T-he Ojibway Salt Mine near Windsor, Ontario, produces almost two million tonnes of97% pure rock salt annually. The salt is mined from the middle F horizon of the Silurian Salina Formation. The salt beds have a gentle dip into the Michigan depositional basin. There is no evidence of deformation. The rock salt is buff coloured and has a number of thin carbonateanhydrire bands. Secondary salt crysrallization occurs throughout the mine.

Jan 1, 1984

The system of keeping geological plans and sections for the Geco Mine at Manitouwadge, Ontario, is described. Special methods employed to save draughting time with-out sacrificing accuracy, such as the extensive use of black line prints, are discussed. The uses made of the plans and sections by the mine planning engineers in their designs of stopes, and by the blast-hole engineer in ~is preparation of blast-hole layouts, are noted. An unusual scheme for portraying the distribution of .copper, zinc and silver values within the ore zone is de-scribed. The method of estimating the grade of ore to be "blasted in each ring of blast holes is outlined, as is the method of estimating the annual ore reserves. The design of an effective but simple transparent geo-logical and mine development model, used as a display for -visitors, is discussed. A large-scale model used for the study of problems in geological structure is also de-scribed.

Jan 1, 1964

By Burrows. A.

Temperature profiles in the lead smelter sinter bed at Xstrata Zinc Mount Isa sinter plant have been measured using a wireless temperature probe. Corresponding sinter samples have been collected for characterization. The sinter peak bed temperatures were found to be in the range of 1000 - 1200 °C. Microstructures and softening temperatures of these sinters have been characterised. Strong correlations have been observed between peak bed temperature and peak hood temperature, and between mean sinter softening temperature and peak bed temperature. It was found that higher peak bed temperature results in higher sinter softening temperature. For the feed material used in the trials, to obtain sinters with mean softening temperatures above 1050 °C, peak bed temperatures above 1130 °C are required. There appears to be a direct correlation between granule size distribution in the feed and peak bed temperature attained. High peak bed temperatures are observed in sinters with narrow granule size distribution.

Jan 1, 2008

By K. Cybulski

Coal dust explosions still remain the main hazard in the coal mining sector, notwithstanding their relatively wide recognition compared to other hazards and the development of effective methods of prevention. Coal dust explosions are still the cause of numerous catastrophes, often leading to fatalities. Fortunately, they rarely occur, and it is for this reason that their hazardous impact is often underestimated. This problem in Poland is being exclusively solved by the Central Mining Institute, Experimental Mine Barbara. Here, basic research on the phenomenon of coal dust explosions and prevention methods is carried out, as well as investigations into the causes and circumstances of past accidents. After 15 years of no coal dust explosion accidents in Poland (1987?2002), a few coal dust explosions have recently occurred, with tragic consequences. These events have taken place not only in hard coal mines, where the presence of dangerous coal dust is the result of common production cycle, and safety measures against coal dust explosions are subject to specific regulations, but also in coal-fired power plants. This is of special concern because prior to 1987, such accidents had been been reported only for coal mines and not for coal-fired power plants. In recent years, two dust explosions occurred in Polish power facilities: the Dolna Odra and Turow power plants. In both cases, coal dust explosions occurred in the fuel supply system, but biomass dust was also involved. The explosions caused significant damage to the systems and buildings. This paper gives description and schematics of the regions of catastrophic coal dust explosions that have occurred in recent years in Poland, as well as the results of post-accident investigations, presenting the coal dust explosion hazard at the accident scene The results specify in detail the state of safety measures against coal dust explosions in light of the relevant regulations in force, including amount of deposited coal dust, content of incombustible matter in coal dust, free moisture content in coal dust, state of coal dust explosion safety zones, and state of explosion barriers. The conclusions from the site inspection and post-accident investigations presented enable us to determine locations of explosion initiation, probable ignition sources, range of explosion flames, and explosion barrier performance. A complete elimination of coal dust explosion hazard at the site of dust deposition is practically impossible to achieve. Similarly, a total elimination of ignition source, which may be related to the occurrence of other natural hazards, equipment malfunction or human errors, is impossible. The examples of tragic events that took place in Polish coal mines and coal-fired power plants highlight shortcomings and mistakes made in terms of assessment and prevention measures taken against the coal dust explosion hazard.

Aug 1, 2013

By Janice Zinck, Ian London

In recent years, the secure supply of critical and technology metals has become increasingly important tomajor industrialized economies that seek to sustain their industrial base and develop advanced technologies, such as clean energy. Canada, with its significant reserves of rare earth element (REE) and other metals, has an opportunity to supply some of the global demand for these materials. However, to transition from promising mineral deposits to marketable products, investment in strategic research and development (R&D) and expertise is needed to address the complex technological challenges around the production, separation and processing of these metals, and to better understand the global market for these key commodities. To this end, in its April 2015 budget, the Government of Canada committed to invest $23M over 5 years to accelerate production of REE and chromite/ferrochrome. The goal of this program, developed in close association with industry, is that Canada contributes a sustainable supply of REE to the global market. The research and development program will provide the technological capacity to establish a Canadian REE industry. This paper will discuss REE R&D advances achieved in the first year of the program in areas of mineral characterization, beneficiation, leaching, separation and environmental management and will highlight the Canadian model of collaboration where industry (e.g. prospective producers, technology companies), government, academia and other stakeholders work closely to ensure that the R&D is targeted, innovative and effectively deployed and commercialized.

Jan 1, 2016

By L. Mohammadi

Outline ?Background on the accident at the Sullivan Mine No.1 Waste Dump ?Holistic approach to understand the reason for accidents (Atmospheric) ?Specific hazards at reclamation sites ?Regular atmospheric risk assessment at reclamation sites ?Fuzzy risk assessment ?Managing risk at legacy sites

May 1, 2010

By Angus D. Campbell

Introduction Gowganda forms part of the general Cobalt area. Its rocks and ores are very similar to those of the other parts of the area. While its total production of silver is only 4 per cent of that of the famous Cobalt silver camp, its 1928 shipments contained 42 1/2 per cent as much silver as those of Cobalt for that year. During twenty years of production, 15,000,000 ounces of silver have been shipped from Gowganda. Of this, over 8,000,000 ounces have been shipped in the past five years. The area has thus made for several years a substantial contribution to the wealth of Ontario. Its future depends to a great extent on the priee of silver, which is now, unfortunately, at a record low price. This paper is a discussion of how the Gowganda ore-shoots occur, together with some notes on the milling of the ores at the Castle-Trethewey Mines. The first part is written in the hope of stimulating further study of the silver occurrences, which may lead to further discoveries. The second part, besides being a matter of record, may be of some use to operators of small mills. The drawings in the several Figures illustrating the text are by W. D. Stroud, mine superintendent of the Castle-Trethewey Mines, the benefit of whose opinions I have had in compiling these notes.

Jan 1, 1930

The concept and practices of co-extraction of coal and methane have emerged in recent years to improve coal mining safety and productivity, utilise methane resources, and reduce fugitive emissions in environments that involve multiple coal seams with low gas permeability. The system of co-extraction integrates two previously separate operations of coal extraction and methane drainage. The coal mining operation reduces the coal seam gas pressure and creates strata fractures that enhance gas migration and capture from mine workings and surrounding coal seams. An effective methane drainage operation produces a consistent and quality clean energy product and, at the same time, reduces the methane concentration in underground workings and the methane content and pressure in the adjacent coal seams. This is a significant benefit in preventing gas explosions and outbursts, and promotes a safer and more productive coal mining environment. In addition, the co-extraction with enhanced utilisation of coal mine methane directly leads to a reduction in greenhouse gas emissions. Presented in this paper are key results and outcomes of a major Asia Pacific Partnership project carried out from 2008?2012 by the Commonwealth Scientific and Industrial Research Organisation in collaboration with Huainan Mining Industry (Group) Co. Ltd., to develop and demonstrate advanced technologies at Pansan mine, Huainan, that promote the concept and practices of co-extraction of coal and methane. A comprehensive approach was adopted to assess fundamental strata and coal seam methane conditions during mining, and optimise mining sequences and coal mine methane capture systems. The project has not only demonstrated a practical approach and procedures of advanced co-extraction of coal and methane systems but also delivered significant benefits and outcomes in improved mining safety and efficiency, increased methane capture and utilisation, and reduced fugitive methane emissions at the Pansan mine. The total mine gas drained increased from 25.36 Mm3 in 2007 to 47.0 Mm3 in 2011, and the mine gas utilisation increased from 4.94 Mm3 in 2007 to 21.15 Mm3 in 2011. The improved methane capture resulted in reduced coal and gas outburst risks and methane concentration levels at the mine workings, provided a safe working environment for coal production, boosted the mining efficiency, and eliminated methane related incidents over the last few years at Pansan mine.

Aug 1, 2013

By C. Han, S. J. Zhou, Y. B. Shen, D. Z. Wei, P. Fang

"Collecting property of two hydroxamic acid collectors have different type of nonpolar structure to hemimorphite has been comparatively studied via monomineral flotation test, and the reason causes different collecting performance has been discussed from the view of relationship between molecular structure and collecting property. The flotation tests results show that C5-9 hydroxamic acid has an unbranched linear alkyl nonpolar group shows better collecting property to hemimorphite than cyclohexyl hydroxamic acid which has a naphthenic nonpolar group. FTIR detecting results show that the adsorption type of collector adsorbed on hemimorphite surface is chemical adsorption. Calculation results of polar group’s geometric structure parameters, polar group’s electron density distribution, octanol-water partition coefficient (logP) and molecular frontier orbital energy show that the key factor caused different collecting property of two collectors to hemimorphite is the logP; unbranched linear alkyl nonpolar group is more conducive than naphthenic nonpolar group to make hemimorphite particle more hydrophobic.INTRODUCTIONZinc-bearing mineral recovered from lead-zinc ores is the main source that people can obtain zinc resource from nature. However, natural sulfide ores are currently getting depleted steadily for the primary zinc source. In order to satisfy the future demand of zinc resource, there is an obvious recognition that the recovery of zinc oxidized minerals from the ores is a crucial alternative (Hosseini & Forssberg, 2007; Navidi Kashani & Rashchi, 2008).But the fact that can’t be ignored is the flotation of zinc oxidized minerals is much more difficult than that of zinc sulfide minerals, which is mainly due to the flotation characteristics of these zinc oxidized minerals such as lower selectivity and higher reagent consumption, as well as complex and variety of lead-zinc ores. Presently, there have been many various beneficiation technologies used for recovering zinc oxidized minerals and dealing with ores for recovering metallic zinc such as flotation and hydrometallurgy (Abkhoshk, Jorjani, Al-Harahsheh, Rashchi, & Naazeri, 2014; Önal et al., 2005). But from an overall perspective, flotation is the most common method used for the beneficiation of zinc oxidized minerals, and there have been extensive investigations conducted on the flotation of zinc oxide ores (Ejtemaei, Gharabaghi, & Irannajad, 2014). Until now, the most well-known method used commercially for the flotation of zinc oxidized minerals is sulfidization with sodium sulfide and flotation with a cationic collector of amines containing from 8 to 18 carbon atoms. However, a major problem for this method is the large amount of fines and slime results in the increase of reagent consumption and promotes the phenomenon of slime-coating. For preclude this negative effect, the de-sliming and processing optimization is indispensible (Peres, Borges, & Galery, 1994; Salum, de Araujo, & Peres, 1992)."

Jan 1, 2016

By J. M. Shneerson

Gipronickel Institute, Saint-Petersburg will The copper concentrate was extracted from copper and nickel matte after its hydrometallurgical treatment and nickel removal. The concentrate containing 60-74% of copper was represented by two principal copper minerals, digenite and covellite. The oxidising leaching of this kind of concentrate was studied at the Gipronickel Institute. The effect of key parameters, such as temperature, oxygen partial pressure and initial solution compound, on the rate of copper dissolution and transfer of sulphur from sulphide to elemental form was investigated. It was shown that at temperatures about 90DC, the sulphur content of covellite converts to elemental form. Under autoclave conditions at 11ODC, the elemental sulphur dissolves as a sulphate-ion. At the temperature range from 50 to 90DC, the copper dissolution rate is in direct relation with temperature. By increasing the temperature to 130DC, this effect is reversed. Based on the research work, a technological flow sheet for the leaching of the copper concentrate was developed.

Jan 1, 2007

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 M. A. Perras, H. A. Kasani, G. Walton

The development of an underground repository for the storage of spent nuclear fuel relies on a multi-barrier system to isolate the used fuel from the environment – ultimately, the biosphere. These barriers include engineered copper and steal canisters, dense bentonite, and the natural rock as well. In order to reduce the potential flow pathway along the excavation induced damage zone, various slots perpendicular to the excavation axis have been proposed. These slots are called cut-off seals and generally are filled with bentonite as it has high swelling potential and very low permeability. Many different geometries have been proposed, but clear guidelines on the selection of the optimum geometry have yet to be developed. In order to assess the optimum geometry, three shapes have been selected for this numerical study, including a trapezoid, a triangle, and a thin rectangular slot. The cut-offs were modelled for a conceptual shaft constructed in the Queenston Formation from Ontario over a stress to strength ratio that has been found at many underground research laboratories. It was found that the excavation of a triangular and thin slot cut-off had the smallest increase in the damage as quantified based on the extensile volumetric strain within the plastic yield zone. Both shapes showed an increase in the damaged zone by 13 cm at a stress to strength ratio of 2.75. The trapezoidal cut-off damage zone increased by 20 cm at the same stress to strength ratio. Further study is required to better define the optimum cut-off shape for wider variety of conditions and other geological formations.

Jan 1, 2020

By A. S. Eve

The detection of magnetic dykes by using magnetic variometers is the oldest application of. geophysics to mining, and is also one of the more simple and certain methods 0f locating such deposits. As a result of recent improvements in the instruments, it is now possible to find the dyke, deter-mine with magnetic variometers its strike and dip', with fair accuracy, and to estimate the approximate depth of overburden when there is no outcrop. The application of electrical methods may be used to distinguish mineral from diabase dykes. The authors have had an opportunity of making surveys with the modern Askania types of vertical and horizontal variometers over magnetic dykes in the Sudbury region. The interpretation of the results has been confirmed by diamond drilling in some cases, and by experiments over models. The variometers used were the standard form of Askania instruments (1). The sensitivity of the horizontal type was 17.2 gammas per division, and that of the vertical variometer double this quantity. To make a preliminary survey of the district, parallel lines were laid off two hundred feet apart running north and south, and readings were taken with the vertical variometer every 100 feet along these lines. This can be done very rapidly, and when an indication of a magnetic deposit is found, the readings may be taken every hundred feet, or less if the size of the deposit warrants smaller intervals. If the deposit is a vein or dyke, the readings along the adjacent lines immediately indicate the strike of the body. Thus the presence and strike of a magnetic dyke, whether of mineral value like the pyrrhotite and nickel deposits of the Sudbury district, or simply a worth-less diabase dyke, is simply and rapidly found.

Jan 1, 1932

By R. C. Bryce, G. S. Martin

"Aur Resources Inc. is the operator of the Louvicourt Mine located 40 km east of Val d'Or. Quebec. Les Entreprises Minieres Redpath Limitée a member of the 1.S. Redpath Group of companies was contracted to construct two vertical mine shaft collars in deep overburden.During the spring of1991 two vertical shaft collars were established in wet, running sand that was in excess of20 m deep. This paper will illustrate the engineering and construction techniques used in establishing these collars and the methods used to overcome the various obstacles that occurred during construction.IntroductionThe Louvicourt copper/zinc/gold/silver deposit is located 40 km east of Val d'Or, Quebec, is adjacent to the former Louvern Mine which operated at depths of 40 m to 850 m below surface (Fig. 1). This deposit was discovered in mid-1989 as the result of systematic exploration and diamond drilling based on a geological model. The Louvicourt project is operated by Aur Resources Inc.The property is being developed to produce 4000 tid with an anticipated life of just over 17 years. Mill start up is scheduled for July 1. 1994, commercial production October I, 1994, and full production by late 1995. The current production plan provides for 24 040 (XX) t averaging 3.89% copper, 1.95070 zinc, 0.039 oz gold per tonne and 0.99 oz silver per tonne, to be mined."

Jan 1, 1994

By M. Bertrand

Oxalic precipitation is usually applied to process radioactive wastes or to recover actinides from a multicomponent solution. Precipitation reactions being highly sensitive to many operation parameters, the computer simulation appears to be a very effective tool to forecast the evolutions of the system subjected to various operating conditions. This study focuses on the tetravalent uranium oxalate precipitation modelling which combines population balance and hydrodynamics. Both experimental and numerical studies are carried out in order to analyse the reactor design influence on the precipitate characteristics. The simulations taking into account primary nucleation and crystal growth are in agreement with experiments.

Aug 1, 2010

By Yi Yang, Mark Zoback

"We report laboratory studies of the time-dependent deformation of core samples from four different formations in the Williston Basin - the Lodgepole formation, the Middle and Lower Bakken formations and Three Forks formation. The laboratory tests reveal varying amounts of viscoplastic deformation in response to applied differential stress. The time-dependent deformation is generally greater in rocks with higher clay and organic content, and can be described by a power-law function. Because the magnitude of the creep strain is linearly proportional to the applied differential stress, we can utilize viscoelastic theory and geophysical logs to estimate the degree to which tectonic stress is affected by viscoplastic stress relaxation. We suggest that viscoplastic stress relaxation results in the Upper and Lower Bakken Formations act as frac barriers during hydraulic fracture stimulation in the Middle Bakken, but the Lodgepole and the Three Forks Formations are not frac barriers.INTRODUCTIONHorizontal drilling and multi-stage hydraulic fracturing in shale reservoirs are critical for successful exploitation of ultra-low permeability shale gas, tight gas and shale oil reservoirs. Characterization of the mechanical properties of the reservoir rocks is essential to understanding the behavior of rocks during drilling and completion. Previous laboratory studies have shown that the timedependent deformation in clay-rich shales can be characterized as linear/viscoelastic deformation (Chang et al., 1997; Hagin and Zoback, 2004a, b; Sone and Zoback, 2013b, 2013c). Sone and Zoback (2013c) showed that laboratory measurements of time-dependent deformation in various gas shale reservoir rocks, and demonstrated that the viscoplastic deformation of these rocks can be characterized by a power-law function. They interpreted the results in the framework of linear viscoelastic theory to quantitatively assess the geomechanical effect of viscous time-dependent deformation over engineering and geological time scales. (Sone and Zoback, 2014) further extended the theory and proposed a viscous relaxation model that can be applied to predict the continuous differential stress magnitude using the geophysical logs. They tested the validity of their model by comparing the stress prediction with the occurrence of drilling induced tensile fractures (DITFs) and the vertical hydraulic fracture penetration observed from microseismicity."

Jan 1, 2015

By Z. Huda

The effect of various percentages of cold-working and recrystallization on the microstructure and hardness of commercially-pure aluminum plate, has been studied. The 'A critical deformation for the aluminum, has been determined. Experimentation involved cold rolling and recrystallization processes followed by quantitative metallographic practice and the hardness measurements. The raw material chosen was a plate of commercial aluminum which was cold rolled to different percentage of cold-work and then recrystallized by heat treatment at 150°C. The critical deformation percentage of aluminum was computed to be around 30% of cold-worked.

Jan 1, 2007