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By J. Stumper

The control of the distribution and movement of liquid water is crucial for increased reliability and durability of PEM fuel cells: whereas the proton exchange membrane requires a minimum amount of liquid water for optimum operation, water excess in the GDL will impede reactant gas access to the catalyst layer thereby reducing performance. In order to understand the relationships between water management on one hand and fuel cell performance and durability on the other, Ballard has been developing a number of minimally invasive techniques that can throw light on the role of liquid water for both cell performance and durability. This paper introduces a novel measurement method that can provide information about the amount and distribution of liquid water under operation. It is shown how the MEA Resistance and Electrode Diffusivity (MRED) method can be used to determine i) the amount of liquid water in the fuel cell, ii) the pure ohmic cell resistance and iii) the O2 -diffusivity of the cathode. Furthermore, through a combination of the MRED method with current mapping it is possible to determine spatially resolved MEA resistance profiles.

Jan 1, 2005

By L. Hacini, N. Van L ê, P. Bacher, D. Thibault

Manufacturer welded components may suffer from high level of residual stresses which can cause premature cracking and decrease the life of the components if they reach values close to the yield strength of the material. In the present work, a robotized hammer peening technique is simulated by an impact machine and the residual stresses generated by the indentation are measured. To better understand phenomena behind residual stresses relaxation by hammer peening, the impact energy level was changed. 304L steel plates were hammer peened with 10 impacts. The contact between the hammer and sample surface was always at the same location. The strains on the surface close to the impact location were recorded during the test using strain gauges to follow residual stresses variations. At the end of the test residual stresses were measured indepth using hole drilling technique at 8mm from the impact center. The micro-hardness was monitored to evaluate the affected zone by the hammer peening. This approach gave a good estimation of the energy and number of blows to be used for efficient relaxation of the manufactured parts.

Jan 1, 2006

By M. N. Pons, F. Ferrari, V. Houzelot, B. Laubie, A. Bani, Université de Lorraine-CNRS LRGP

"More than 400 plants in the world are able to accumulate nickel in their aerial parts at concentrations higher than 10 g per kg of dry biomass. Then, nickel (Ni) can be recovered from the biomass of these hyperaccumulator plants. Agromining is a chain consisting in growing such plants and recovering metal and has been developed thanks to the combined know-how of agronomy and hydrometallurgy. Plants can be grown on serpentine soils, containing rather high concentrations of Ni, on sterile heaps or on contaminated soils. This crop enables us to extract Ni from secondary resources, and to improve soil quality by lowering its metal content. For example, Alyssum murale can be grown at the field scale in the Balkans, at yields corresponding to 110 kg Ni per hectare.Hydrometallurgical processes have been designed from the lab scale to the pilot scale to produce nickel salts: ANSH (ammonium and nickel sulphate hexahydrate), nickel sulphate, acetate, etc. and so on. These salts are used for surface treatment and in the paint and chemical industry. Ni salts are prepared from ashes, after plant calcination. Processes are based on the conventional methods of hydrometallurgy: acid leaching followed by different precipitation steps. These processes will be presented, as well as the pilot scale design. A life cycle assessment has been performed and clearly shows the environmental interest of this approach as a potential part of an anti-erosion strategy. An economic assessment has proved process feasibility and the final step is the launching of a start-up. At the moment, the approach is widened to other metals (cadmium, cobalt) and rare earth elements (REEs)."

Jan 1, 2016

By A. Hayatdavoudi, K. G. Sawant, F. Boukadi

"In this work, we found that contact between shale and water results in development of micro fractures. Based on results of experiments on Pierre shale, we conclude that appearance of micro fractures begin with saturation of capillaries, ionic and diffusive transport of water into the shale clays and once capillaries are saturated, the cause of micro fracture propagation is the conversion of ionic activity/exchange to excess pressure that did not exist before fracking. Based on these findings, the spread of micro fractures appear to be a time-dependent phenomenon which has not been addressed in the existing macro/micro fracture models.INTRODUCTIONShale has often been involved as a hazard in drilling operations. This hazard can be defined as “destabilization” of shale. When contacted with water-based drilling fluids, some shales readily swell and sometimes, cause the wellbore to cave-in, slough, wash-out, close, and pack-off, impeding the drilling by sticking the drill-pipe. However, once drilling reaches the desired depth or length, the casing is set, cemented, and perforated, and then actually we wish to initiate fractures and destabilize the shale formation, using hydraulic fracturing.Clays constitute a major portion of minerals in shale. These clays contain a large amount of free energy which is the main factor for “slick” water adsorption/absorption. In fact, the reason for using “surfactants” in hydraulic fracturing fluids is to make the penetration of the fluid into the capillaries much easier, thus water meets with less resistance to enter the small capillaries. Also, the result of high capillary suction pressure is due to small Angstrom size capillaries, smaller pores and presence of ions and hydrateable metal atoms. The free energy is thus, related to all the above mentioned and other affects. Capillary pressure, osmotic pressure and other pressures are responsible for creating the micro-fractures in shale, thus, increasing the network of micro-fractures which leads to more gas production. The objective of this study is to evaluate the pressures of the individual ions which are released by the diffusing “slick” water into shale. These pressures would be added to the above mentioned capillary pressure, osmotic pressure, bacterially-induced pressures, chemically-induced reaction pressure, pressure due to exchangeable ion-transport, pressure due to release of free energy of solvation and eventually to the pore pressure as suggested by Terzaghi’s equation."

Jan 1, 2015

By S. Hosseinpour

Chromate conversion coatings (CCCs) are usually applied to these alloys to enhance their resistance to localized corrosion and to improve paint adhesion. The special properties of these coatings such as their low electrical contact resistance (ECR) make them suitable for satellites. This study is aimed to develop advanced CCCs with the proper appearance, morphologies and surface roughness and to evaluate their role on the ECR and thermo physical properties on hardened aluminium alloy of Alclad-7075-T6. Coating characterization was performed by means of scanning electron microscope (SEM) and atomic force microscope (AFM). ECR of coatings were measured by special laboratory designed instrument and a and c were measured by Emissometer and Reflectometer respectively. In addition, corrosion performance of the CCC-coated alloys was determined by 168 hr exposing to salt-spray testing in accordance with ASTM-B117. The results of accomplished experiments on the developed CCCs in this study have been agreeable concerning available acceptability criteria for satellite surfaces.

Jan 1, 2007

By Derrin A. Auerswald, Jacolien P. Wyethe, Nanne M. \/egter

Base and precious metal refineries often produce effluent solution and slurry streams containing between 50 mg/L and several grams per liter of base metals. Metals have historically been precipitated from these streams with lime to produce effluent streams at pH values between 8 and 9. This effluent treatment process generally does not remove alkali and alkali-earth metals or halides efficiently and with more stringent environmental legislation, more sophisticated effluent treatment plants must be considered which could for example incorporate sulphate removal with ultra-filtration, or the SavminTM process, followed by reverse osmosis for the removal of halides. The flowrates of effluents are often high and if base metals can be recovered before neutralization, the revenue generated from this stream can reduce the cost to produce clean water significantly, and in the case where high concentrations are disposed of, result in a profitable operation. As an add-on to an existing the plant the recovered metal is upgraded and recycled to the plant, but the production of a saleable metal can also be considered. Technology selection for metal recovery depends on the composition and flowrate of the effluent, but could incorporate resin-in¬pulp or other ion-exchange technology; precipitation as sulphides, hydroxides or carbonates; or solvent extraction. This paper describes, as a case study, the technology selection process and uses data from Zincor. Zincor is a division of Exxaro Base Metals (Pty) Limited, a subsidiary of Exxaro Resources Limited.

Jan 1, 2011

By P. Wanjara, M. Xiao

During fusion welding of aluminium alloys, the avoidance of defects (such as porosity, oxides, hot cracking, undercutting) as well as the ability to optimize the microstructure-property characteristics in the assembly are critical for the stringent manufacturing specifications in the aerospace industry. In this work, aluminium alloy (AA) 2024 was electron beam welded autogenously as part of a study to determine the influence of parametric conditions on the characteristics of the heat affected and fusion zones to obtain optimal welding conditions. In particular the evolution in the weld geometry, microstructure and mechanical properties were examined as function of the processing conditions, including beam current, beam focus, beam oscillation, linear heat input and welding speed. For optimized parametric conditions, microstructural examination of the joints revealed narrow fusion and heat-affected zones comprising of dendritic structures without the occurrence of defects that enabled a maximized joint efficiency.

Jan 1, 2006

By P. V. Barr, Y. -H. Li, A. P. Watkinson

Subsequent to a campaign of pilot-kiln trials of firing bio-oil and natural gas, scale-up to commercial lime kilns was made using an in-house mathematical kiln model. Both dry limestone and lime mud kilns of 3.5 m OD. by 100 m length were used for bio¬oil firing simulations. Comparisons were made against natural gas firing on the basis of specific firing rate, off-gas volume, energy consumption and overall lime quality. Model simulation results indicate that conversion from natural gas to bio-oil with no productivity loss will increase energy comsumption by about 7.5% and total off-gas volume by about 8%. Alternatively, a 6% decrease in productivity would be expected if off-gas volume is maintained constant. The calculations are sensitive to deviations in the lower heating value (LHV) used in the simulations. A 5% increase in the LHV of the bio-oil, which could result from a 3% decrease in the moisture content, reduces the energy penalty to 2% coupled with a slight reduction in off-gas volume.

Jan 1, 2004

By E. H. Holm

"This paper is a market-oriented review of the industry's present and forecasted performance, considering some of the principal factors influencing natural resource development. The author illustrates the steady consumption growth of nickel, and stresses the need for a quantitative long-range approach to production, consumption and the supply/ demand balance on a worldwide basis. Objective consideration of this data exposes some popular misconceptions. The possibility of near-term undersupply of nickel is discussed in relation to historically rapid changes in inventories and demand patterns. What is the significance of the increasing reliance on lateritic sources? New• facilities, new processing methods and new product forms are illustrated as further evidence of the industry's determination to satisfy the needs and preferences of nickel consumers. Examples indicate how product forms must accommodate to fast-evolving end-use technology. A review of nickel's price performance is used as a base from which to explore tomorrow's price trends."

Jan 1, 1972

By Olav Mejia

The rising energy costs and environmental considerations in mining necessitate the development of energy-efficient copper and gold processing plants. This paper presents an analysis of technical strategies aimed at reducing energy consumption in these plants. Key approaches include the integration of advanced ore sorting technologies, High Pressure Grinding Rolls (HPGR), Coarse Particle Flotation (CPF), and high-intensity flotation. Ore sorting enables early-stage waste removal, reducing the downstream processing load and associated energy use. HPGR technology, recognized for its energy efficiency, contributes to significant energy savings in comminution circuits by reducing reliance on traditional grinding methods. CPF technology further optimizes flotation performance by enabling the recovery of larger particles, thereby decreasing the need for fine grinding and reducing overall power demand. High-intensity flotation units enhance separation efficiency and mineral recovery in a compact footprint, offering further reductions in energy consumption. Together, these technologies provide energy saving opportunities to achieve a more sustainable and economically viable processing operation. This paper evaluates the effectiveness of each method, highlighting their potential impacts on energy consumption, operational efficiency, and cost-effectiveness in copper and gold processing

May 4, 2025

By W. Cholewa, T. S. Golosinski, J. Wedzicha

"Power requirements of belt conveyor drives are usually estimated based on the calculated belt tension which equals the sum of unit resistances to motion which the belt has to overcome. In most situations, the value of various unit resistances can be accurately predicted using published information (5,6,8,12). A simpler approach calls for use of standard formula and tabulated values of related factors which reflect various features of both the conveyor and the transported material (2,3,7) . None of these approaches is reliable when materials with unique properties are conveyed, nor if applied to conveyors working in extreme climatic conditions. Such is the case of oil sand mines in northern Alberta.There the bitumen content of oil sand causes it to behave in a unique manner. Furthermore the conveyors operate year around, with winter temperatures often lower than - 40°C. It was the objective of presented investigations to quantify the power requirements of conveyors, and related resistance to motion for the conveyors used in oil sand mines during winter operations.The other objective was to quantify the drive power requirements of oil sand conveyors during start-up. These requirements are usually much higher than those during norm al operation, and their quantification is of paramount importance for operation of large conveyors."

Jan 1, 1992

By P. Woo, N. Brodusch, R. Gauvin, H. Demers

For developing new technologies, it is important to characterize the microstructure of materials with high spatial resolution at the nanoscale. To achieve high resolution, field emission scanning electron microscopes (FE-SEM) were developed. These microscopes allow working at low accelerating voltage, below 5 kV, to take advantage of the reduction of the interaction volume with accelerating voltage. Furthermore, their higher gun brightness compared to conventional thermo-electronic emitters, allow a probe size at the nanoscale. At low accelerating voltage, the emission volume of backscatter and secondary electron (SE) of the type II signals approach that of SEI signals. However, it is not enough to reach the highest resolution. A magnetic field above the sample improves the spatial resolution by collecting mostly high-resolution signals. In addition, the energy-filtration of the electron signals allows selecting the type of contrast detected: topographic, compositional, or crystallographic. The development of these new technologies permits to extend the imaging capabilities of the SEM towards new nanoscale applications.

Jan 1, 2014

By M. A. Golozar

Partially stabilized zirconia (PSZ) has been proven to be an excellent candidate as a thermal barrier coating (TBC) for hot sections in, for instance, heat or internal engines and gas turbine parts. The main functions of these coatings are reduction of heat losses, reduction of fuel consumption, increasing efficiency, and extending durability and life. One of the main problems involved is wear behavior in the development of such coatings for these applications. Using air plasma spraying (APS) technique, conventional and nanostructured 8 wt % yttria partially stabilized zirconia (Y-PSZ) coatings were deposited on austenitic stainless steel (AISI 304) disc-shaped substrates. The coated substrates were subjected to pin-on-disc wear tests, using 10 mm silicon nitride and zirconia balls as the pin. The coefficient of friction was recorded in real time. The weight loss of coated substrates was measured. Coatings were characterized before and after being subjected to wear testing by various techniques including optical microscopy, scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDX) and X-ray diffraction (XRD). Effects of various experimental parameters such as wear distance, test temperature, and counterface material were also investigated. Results obtained revealed that, regardless of experimental conditions applied, the nanostructured zirconia coating shows better wear and tribological properties than those of the conventional one.

Jan 1, 2005

By Hong Zhong, Shuai Wang, Gang Zhao, Lanqing Deng, Guangyi Liu

In this paper, three novel surfactants containing double reactive centers(-CONHOH and –CONH-), double hydrophobic groups were designed and synthesized as collector for separation of diaspore and aluminosilicate minerals, such as N-(4-(hydroxyamino)-4-oxobutyl)octanamide (HA-8), N-(4-(hydroxyamino)-4-oxobutyl)decanamide (HA-10) and N-(4-(hydroxyamino)- 4-oxobutyl) -dodecanamide (HA-12). The adsorption mechanism of N-(4-(hydroxyamino) -4-oxobutyl)alkylamides (HA) onto diaspore was also investigated by FTIR spectra, zeta potential measurement and DFT. The flotation results demonstrated that three collectors all exhibited superior collecting power to diaspore and selectivity against kaolinite and illite, and could effectively realize flotation recovery of diaspore from bauxite ores contained aluminosilicate minerals under neutral conditions. Moreover, HA-12 was a superior collector than other two collectors for bauxite separation. The results of XPS, FTIR spectra and zeta potential illustrated that at around pH 6.0, HA might chemisorb on diaspore surfaces through Al-O coordination bonds formed by binding its –C(=O)NHOH or –C(=O)NH– chelate groups with aluminum atoms on diaspore surfaces. HA’s unique properties, such as characteristic bond patterns onto diaspore surfaces, double hydrophobic groups, and intermolecular hydrogen bonds between neighboring HA molecules coated on diaspore surfaces, rendered it to be a superior flotation collector for diaspore.

Jan 1, 2016

By Les Philips

National Institute for Safety and Health?s (NIOSH, USA) Office of Mine Safety and Mine Safety and Health (OMSHR) has definitions for: -Proximity Detection as detection of personnel, vehicles and other objects near a machine using some type of sensor technology -Proximity Warning (aka Collision Warning) as detection of personnel, vehicles and other objects near a machine resulting in alarms that ?Warn the operator only ?Warn the operator and nearby personnel (two-way) -Collision Avoidance as the processing of sensor information resulting in control signals or actions that alter machine status/movement to avoid a collision by ?Computer control ?Human control

May 1, 2013

By J. Oliver, B. Wilson, 10

"Red Dog is one of the world’s largest zinc producing mines and a significant producer of lead and silver. While some of the operational challenges relate to the mine’s location in a remote part of Alaska, there are also challenges in the mineral separation process. Recent processing upgrades have included the installation of two M5000 IsaMills to improve the zinc regrind circuit and of one Jameson Cell to improve the pre-flotation circuit. Relatively fine grinding is required to achieve efficient mineral separation at Red Dog, but while fine grinding aids in the production of high grade concentrates, it also creates challenges in the efficient recovery of fine minerals. Over half of the lead lost to the lead circuit tailings, as well as almost half of the zinc lost to the final tailings, is in the finer size fractions (<10 µm). The high pulp density experienced in the pre-flotation and lead rougher circuits also causes significant entrainment loss of lead and zinc to the pre-flotation concentrate and of zinc to the lead concentrate. To help improve fine mineral recovery, Red Dog has recently plant tested and installed magnetic conditioning technology in the flotation circuits. The equipment aggregates fine paramagnetic sulphides and selectively increases their flotation recovery. This paper outlines the testing and positive results at Red Dog.INTRODUCTIONRed Dog is the largest zinc mine in North America and represents approximately 29% of North American zinc concentrate production. The mine is located in northwest Alaska, approximately 100 miles north of the Arctic Circle and 50 miles inland from the Chukchi Sea. The remote location makes the mine accessible only by air or seasonally by ocean-going barges. Red Dog is a partnership between NANA Regional Corporation Inc, the land owner and Teck Alaska Incorporated, the operator of the mine. Red Dog Ore and Mineralogy The Red Dog deposit is a rich sedimentary exhalative (sedex) zinc-lead-silver deposit. The main minerals present in order of abundance are: quartz, sphalerite, pyrite, barite and galena. Production began in 1989 with mining of the Main deposit. Between 1989 and 2012, approximately 55.6 million tonnes of ore with an average grade of 20.5% Zn, 5.6% Pb, and 97 g/t Ag was mined from the Main deposit. Subsequent to the development of the Main pit reserve, two additional open pit deposits were discovered: Aqqaluk and Qanaiyaq. The first blast in Aqqaluk occurred on June 4, 2010. As of December 31, 2014, the Aqqaluk deposit reserve is an estimated 45.7 million tonnes of ore with an average grade of 15.1% Zn, 3.9% Pb and 71 g/t Ag."

Jan 1, 2016

By Rodolfo Zanella

Au/TiO2 catalysts were prepared by deposition-precipitation using NaOH (DPN) (~3 wt % Au) and urea (DPU) (~8 wt % Au), and calcined at various temperatures between 100 and 400 °C. They were characterized by UV-Visible, XANES, EXAFS and TEM. Their activity were tested in the reaction of CO oxidation at 5°C. After preparation, the gold species are in the oxidic state III. They begin to transform into metallic gold under air at ~100 °C for DPN and ~150 °C for DPU. At 200 °C, all the gold is metallic for the two preparation methods. The particle size increases from 1.5 to 3.5 nm with the calcination temperature. The catalytic activity for CO oxidation increases with the percentage of metallic gold, and it is maximum at 200°C for both types of samples. The activities (per mole of Au) are the same for the two types of catalysts. At higher temperatures, the catalytic activity drops. The decrease of activity is mainly due to a change of particle shape with the calcination temperature rather than to the increase of the particle size. At a calcination temperature of 200°C, the particles present small facets with rounded parts, and their outer surface contains a large proportion of low coordinated sites (steps and corners) while at high temperature of calcination, they are truncated octahedra with smooth facets.

Oct 1, 2003

By K. C. Corin, Z. G. Song, J. Y. Liu, M. W. Zhang, State Key Laboratory of Mineral Processing-BGRIMM, J. G. Wiese

"In the present study effect of grinding media on flotation of two mineral systems have been investigated, viz. sulphide minerals (including a pure chalcopyrite and pyrite mineral, and two different base metal sulphide ores), and oxide minerals (quartz, hematite and cassiterite). It was shown that mild steel media milling produced lower recoveries in the case of chalcopyrite and pyrite, as compared to the case of milling using ceramic media. For oxide minerals, the effects of using mild steel media as opposed to ceramic media were not as significant as was for the sulphides, although, after mild steel milling, at acidic pHs their recoveries were significantly reduced. For two base metal sulphide ores, viz. Nkomati and Dexing ores, the differences resulting from different milling media , although marginal, were opposite for each of these ores.For oxide minerals XPS showed that oxides and hydroxides of iron (e.g. FeOOH) adsorbed on the surfaces of the minerals. In the case of the Nkomati ore, adding Fe2+ or F3+ ions after milling with chrome steel media resulted in reduced talc (gangue) recovery, but increased water recovery and reduced concentrate grades. Further investigations are currently in progress to examine the Fe ions effect on the talc surfaces and froth properties.INTRODUCTIONGrinding of ores is necessary to liberate the valuable minerals from its gangues to allow for their selective recovery during mineral processing such as flotation. The grinding process inevitably involves contact of the ores with the surface of the grinding device and the grinding media. Accompanied by grinding, several phenomena can occur including the grinding medium wear, formation of precipitated species on the ore surfaces, chemical reaction, galvanic effects, changes in the Eh of solution, etc. There is a considerable body of literature on the differences observed in the flotation of various ores after milling using various grinding media. Laboratory studies have used balls or rods made from mild steel, ceramic, stainless steel or chrome steel to investigate the effects of different grinding media on mineral flotation. It is found that the interactions between the ore and the grinding environment can affect flotation separation of sulphide (Wei and Sandenbergh, 2007; Bruckard, 2011), oxide (He et al., 2014) and carbonate minerals (Song, 2009 and 2010). For example, mild steel milling produces relatively high concentrations of Fe ions in the pulp, affecting the recoveries of minerals compared to the case of ceramic media. On the other hand, the stainless steel media or chrome media are reported to be beneficial to the recovery of sulphides, when compared to the cases of using mild or carbon steel media (Rey and Formanek, 1960; Peng et al., 2003a,b; Huang and Grano, 2006; Bruckard, 2011). It is not clear, however, whether these Fe ions may affect the surface properties of the minerals involved or the general pulp/froth behaviour and hence their floatability. In addition, in the study of an low-S PGE ore carried out by Miettunen et al. (2012), forged media grinding in the CO2 atmosphere led to the highest Pt and Pd grades and recoveries, but the high chrome grinding media gave lower flotation recoveries than those using the forged media."

Jan 1, 2016

By M. R. Julien

"The geomechanical behavior of rocksalt shows very distinctive features. The response of this most ductile of all low porosity rocks is dominated by inelastic processes that are strongly time- and historydependent. These characteristics must be taken into account when analyzing underground openings. Different constitutive models have been proposed and used for this purpose, and this paper presents the general formulation and applications of one of these. The SUVIC model relies on a unified approach with internal state variables producing mixed hardening to represent the inelastic behavior, which lead to specific solutions for plasticity and creep. The model equations have been implemented into a finite element code to perform numerical analyses. Simulations results are presented to show that this model captures essential aspects of rocksalt behavior under simple and complex laboratory testing conditions. Simulations are also conducted to analyze the response of underground openings. INTRODUCTIONPredicting the response of man-made excavations in rocksalt can be quite a challenge as it requires a reliable constitutive model to represent the material behavior. This softest of all low porosity rocks shows a highly non-linear inelastic behavior, very sensitive to history and rate effects (e.g. Senseny et al., 1993; Cristescu & Hunsche, 1997; Julien, 1999; Wittdke, 2014). The many deformation (micro) mechanisms acting locally in rocksalt make the construction of appropriate constitutive equations quite complex. Nonetheless, there have been significant progresses made over the last two decades or so; many of these developments have been included in a series of specialized Conferences Proceedings (Ghoreychi et al., 1996; Aubertin & Hardy, 1998; Cristescu et al., 2002; Wallner et al., 2007; Bérest et al., 2012)."

Jan 1, 2015

By J. W. Senn

A magnesium alloy modeled after commercial alloy WE54 was thermomechanically processed and characterized to understand the mechanisms by which its texture can be randomized, as reported by Ball and Prangnell [1]. Samples were deformed in plane strain compression to prescribed strain levels at temperatures high enough to prevent cracking and then recrystallized. The deformation texture is very similar to that observed after plane strain compression (e.g., rolling) of other Mg alloys, such as common AZ31. However, the texture can radically evolve during recrystallization. Annealing above the precipitate solvus temperature results in a nearly random recrystallization texture where the initially strong basal texture is completely eliminated. Annealing below the solvus temperature produces a recrystallized texture similar to conventional Mg alloys, i.e., a weakened basal texture. If this same material is then annealed above the solvus to promote grain growth, a randomized texture evolves, which is similar that of samples simply recrystallized above the solvus. It is hypothesized that a sort of preferred growth mechanism, whereby grains with random orientation grow faster than those with the original basal texture, contributes significantly to the texture randomization observed in wrought magnesium alloys containing rare earth elements.

Jan 1, 2006