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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

By E. Krause

The oxidation of Fe(II) with S(IV) and oxygen can be used advantageously in leaching systems requiring both Fe(III) and sulfuric acid; e.g., heap leaching of sulfide-containing ores or concentrates. The oxidation of Fe(II) with SO2/air is several orders of magnitude faster than with air alone; rates of up to ?20 g/L'h were observed at 25°C. The reaction proceeds via an intermediate orange-red mixed-valence Fe(II)/Fe(III) sulfite complex, which is present at an essentially constant concentration throughout most of the oxidation process. The oxidation rate of Fe(II) is approximated by the formula -d[Fe(II)]/dt = k [S(IV)] [02]0'3. The concentration of the mixed-valence complex, and thus the iron oxidation rate, decreases with increasing acidity. Certain impurities, such as SCN- and thiourea, negatively affect the rate. The oxidation reaction 2Fe2 + SO2 + 02 4 2Fe3+ + S042- is accompanied by the side reaction H20 + SO2 + 1/202 4 H2SO4. The side reaction becomes particularly important at low temperatures and whenever the oxygen mass transfer is insufficient with respect to the rate of addition of S(IV). Thus, effective oxygen mass transfer is essential for achieving high oxidation rates with minimal acid formation. The activation energy was estimated as 141 kJ/mol over the temperature range 10-35°C.

Jan 1, 2006

By Michael J. Beus

The National Institute of Occupational Safety and Health-Spokane Research Laboratory (NIOSH-SRL) have developed a Shaft Conveyance Monitoring System (SCMS). Assessment of current hoisting technology has shown that monitoring wire rope tension and conveyance position and load directly from the skip or cage top offers several significant safety, production, and maintenance advantages. The SCMS consists of conveyance position and guide displacement sensors, a battery power supply and charging system, and a new sensor to measure hoist rope tension. This device provides a warning of the occurrence of ?slack rope? a particularly dangerous condition. A 2.4 GHz radio link transmits data to the hoistroom. A reduced scale hoisting test facility has been constructed to test these components prior to field trials. The advantages of monitoring wire rope tension and conveyance position and load directly from a skip or cage top will be discussed. Field tests are underway in full-size shafts to refine the concept and evaluate long-term reliability and maintenance requirements. Application of this technology may result in decreased maintenance costs as well as safer, more productive hoisting operations.

May 1, 2001

By Georges Houlachi, Akram Alfantazi, Maysam Mohammadi

Manganese ions in zinc electrowinning electrolytes form a protective MnO2 layer that ultimately decreases Pb contamination in the zinc product. In this study, the effect of dissolved Mn2+ on the electrochemical performance of Pb, Pb-Ca and composite Pb-MnO2 anodes was investigated. The properties of the MnO2 layer formed on these anodes were studied and compared. Potentiodynamic polarization and cyclic voltammetry experiments were performed in 180 g L-1 sulphuric acid to study the electrochemical reactions occurring on the anodes. The anodes were subjected to galvanostatic polarization at 50 mA cm-2. The morphology and uniformity of the MnO2 layer on the anodes were examined using scanning electron microscopy (SEM). Experimental results revealed that the MnO2 layer formed on the composite anode was more compact and uniform compared to that formed on the Pb and Pb-Ca anode. It was also observed that the cell mud formation rate, and consequently manganese ions consumption, depended on the anode type. Although initial formation of the MnO2 layer decreased the oxygen evolution overpotential, its growth might negatively affect electrocatalytic activity of the anodes.

Jan 1, 2014

By M. Mirnezami, J. A. Finch, S. Uddin

A fast, reliable and practical way of measuring zeta potential using sedimentation potential method is proposed. A cell was designed along with the instrument control software to determine the required variables simultaneously i.e. sedimentation potential, specific conductivity, volume fraction of solid as well as pH. High purity alumina and silica powders were used as test samples. Measured zeta potential using the proposed technique was comparable with the results by electrophoresis.

Jan 1, 2009

By Carrasco .. P. J. A., R. Parada, I. Saavedra, F. Parada, R. Parra, E. Balladares

In most of the smelters, the management of flue dust has a double objective: the control of minor elements in the anodes and the management of volatiles compounds that can cause contamination due to fugitive gas emissions. This is a special concern when high content of Va elements (As, Sb & Bi) are present in concentrates. We present the results of the experimental study to prove the principle of a novel process that recovers, via volatilization, the As, Sb and Bi in the flue dust as gaseous sulfides, due to a previous sulfidization. In the case of as control any further classical treatment for its stabilization is possible from the gas. The clean calcine can be returned to the smelter avoiding any concentration of these minor elements in the circuit. This process is now tested at pilot scale and shows better indices on carbon footprint than the classical hydrometallurgical process for flue dust.

Jan 1, 2011

By E. C. Goodhue, R. D. Coleman, I. E. Puddington, A. F. Sirianni

Iron ore samples containing apatite are fractionated to acceptable products by spherical agglomeration methods. The phosphorus is upgraded by a factor of 10 at an elevated pH. High-grade iron products are obtained in good yields from the tailings in a second step of the operation. The grade of the phosphorus separated appears to reach a maximum at about pH = 10; recovery of iron decreases below about pH = 4. Both the recovery and grade of iron are found to be reduced sharply above about pH = 8.

Jan 1, 1968

By W. B. Boggs

A paper describing the Noranda smelter was presented at the 1930 annual meeting of the Institute (1). A lacer article appeared in the Trans-actions of the A.I.M.&M.E. in 1933. Since that time there have been many changes and improvements in plant operation and it is the abject of this paper to give an account of developments up to the beginning of 1939. The Noranda smelter was built originally for a capacity of 30,000 tons a month. At present, the average tonnage being treated is 110,000 tons a month, the tonnage of custom ores alone amounting to almost the total rated capacity of the original plant. This increase has been accomplished by increasing the capacity of the reverberatory furnaces from 700 tons of solid charge per furnace day in 1928 to 1,500 tons per day at the present time. In 1935, it appeared chat the limit of furnace capacity had been reached at about 1,300 tons of charge per day because of the short life of the sprung silica arches. However, the adoption of the suspended magnesite roof, which had been developed at the Flin Flou smelter of the Hudson Bay Mining and Smelting Company, overcame this difficulty and it is believed that the limit of the capacity of the present reverberarory furnaces has not been reached. A brief account of the changes to equipment in the various departments will be given, followed by a description of the more important features of present smelter practice.

Jan 1, 1939

By H. Attia, S. Engin

This paper presents a practical approach for determining the optimal spindle speed and the depth of cut in a milling operation within the ever-increasing economic and technical constrains. Analytical modeling and experimental work has been carried out to predict chatter in such operations. The stability lobes determined from this analysis were then used as a constraint in the optimization of the cutting process. The optimal cutting conditions are determined for two different objectives: maximum metal removal rate and minimum cost per unit. It is demonstrated that this approach can be generalized to impose multi-level constrains, e.g., surface integrity and machining accuracy. The approach presented in this work was examined and validated on three NC milling machines. The productivity improvement, cost reduction, while respecting part quality requirements, is demonstrated.

Jan 1, 2006

By Yve Potvin, Fabien Miller, Deni Jacob

"The potential benefits of measuring the volume of excavated open stope are enormous. By comparing the actual excavation of the orebody contour, it is possible to determine the “real"" amount of mining dilution, as well as the ore left in place. Noranda Technology Centre (NTC) has developed a stope survey system that allows for rapid and efficency measurement of underground excavation volumes. The system comprises a commercial laser (EDM), a set of lightweight rigid rods, an automated scanning device, a hand-held data logger and Autocad-based software for volume calculation and drawing manipulations. This system is an invaluable tool for the optimization of mining practices and could also be used for the delineation of caving areas. IntroductionDilution is the most common and devastating mine disease. In some instance s it could systematically cripple the profitability of an operation, and in more extreme cases, it could become a terminal disease. The Northern Miner Journal (1988) reported that many operations have closed because of uncontrolled dilution, before they even completed their first year of production. Other studies (Pakalnis, 1986) have shown that approximately 40% of all underground operations have more than 20% dilution. Considering that every ton of dilution costs in the neighbourhood of $25, the total direct cost of dilution to the Canadian mining industry may easily exceed one hundred million dollars per year.The dilution problem has been a major concern to Noranda Minerals for some time and in 1984 a comprehensive geomechanics research program was created at the Noranda Technology Centre (NTC) in Pointe-Claire, Quebec. New empirical stope dimensioning techniques, improved cable bolting techniques and sophisticated ground control instrumentation projects (among others) contributed to improve the situation at Noranda.A new tool which can have a very significant impact on the ""war"" against dilution is being developed by the Noranda Technology Centre. The laser stope survey system allows for a rapid, precise and efficient measurement of underground excavation volumes. By comparing the excavation planned with the volume excavated, it becomes possible to determine the ""real"" amount of mining dilution as well as the amount of ore left in place. This system may also allow for early detection of a dilution problem. As with other diseases, early detection provides the best chance for a fast and total recovery."

Jan 1, 1992

By O. G. Olvera, E. Asselin, D. Rival

Particle concentration distributions in a leaching tank have been estimated using a novel experimental approach that takes advantage of the galvanic interactions that occur between pyrite (FeS2) particles and a Pt electrode. The collision of FeS2 particles with Pt changes the open circuit potential measured with the electrode due to galvanic interactions. To discern particle collisions with the Pt electrode from experimental noise a simple analytical procedure was first adopted although the use of techniques involving frequency domain analysis is also briefly presented and discussed. Although this method is still under development, it is simple to implement and can yield valuable information regarding the hydrodynamic behavior of solid particles in stirred tanks in very short times. Finally, the advantages and drawbacks of the technique are discussed.

Jan 1, 2014

By T. Donkin, B. Patterson, M. I. Guthrie, J. T. Ross

"Interest in the use of particle-based ore sorting has increased significantly with recent advances in sorting technologies and higher capacities per unit. Particle-based ore sorting has the potential to provide great value in processing lower grade ores from mines while delivering higher grades to the mill, as well as in upgrading waste rock into ore. Typically the focus is on the amenability of the ore to ore sorting and associated reductions in energy, water, and consumables utilization. However, layout significantly affects the installed cost of a processing plant, and the impacts on layout from fitting an ore sorting circuit into the plant plan need to be carefully considered. This paper examines processing plant layout considerations that play an important role in ore sorting projects, including additional crushing and screening requirements, transport of rejected material back to the waste stockpile (mine fleet requirements), and effects on the processing plant footprint. ¦ KEYWORDS Cold climates, Ore sorting, Plant layout RÉSUMÉ L’intérêt porté à l’utilisation du tri granulométrique du minerai a considérablement augmenté au vu des récents progrès réalisés en matière de technologies de triage et des capacités supérieures par unité. Le tri granulométrique du minerai offre une plus-value intéressante en termes de traitement du minerai à plus faible teneur extrait des mines ; il permet par ailleurs l’acheminement vers le concentrateur de minerai à plus haute teneur et la revalorisation des stériles dans le minerai. On met généralement l’accent sur la susceptibilité du minerai au triage et sur les réductions connexes en termes d’utilisation de l’énergie, de l’eau et de biens consommables. Cependant, l’aménagement physique de l’équipement a une incidence non négligeable sur le coût installé d’une usine de concentration, et les répercussions sur l’aménagement de l’installation d’un circuit de triage du minerai dans l’usine doivent être soigneusement examinées. Cet article étudie les considérations relatives à l’aménagement de l’usine de traitement qui jouent un rôle important dans les projets de triage du minerai, et notamment les exigences supplémentaires en matière de concassage et de criblage, le transport de matériau résiduel jusqu’à la pile de stockage des déchets miniers (nombre de camions requis dans le parc minier) et les effets sur l’empreinte de l’usine de traitement. ¦ MOTS CLÉS aménagement de l’usine, climats froids, triage du mineraiINTRODUCTION Ore sorting has been practised throughout history. An early report by Agricola in 1556 documents how metallic and non-metallic minerals were extracted from rocks by laboriously breaking them with hammers and picks and hand-picking selected material with higher grade (Hoover & Hoover, 1950). The concept has not changed, but sorting technology has evolved significantly over the last 20 years"

Jan 1, 2019

By M. Jorgensen, I. Markland, D. Shuck

"The McLaughlin Mine owned by Homestake Mining Company is located 70 miles northeast of San Francisco in California's coastal range. The mine began operations in February of 1985. The mill currently processes 3,000 short-ton per day of sulfide ore that has an average grade of 0.15 ounces of gold per ton, plus another 3,000 tons per day in a newly completed oxide circuit. Annual production from the mine totals over 200,000 ounces.The sulfide ore extraction process involves three basic steps, grinding, oxidation of sulfide minerals in an autoclave, and cyanide leaching for recovery of gold in a carbon-in-pulp circuit. This process, which incorporates a new technology where oxidation of sulfide minerals is conducted prior to cyanide leaching to facilitate gold recovery, was successful from start-up. However, limitation in the grinding mills initially limited sulfide tonnage throughput.This paper discusses modifications made in the grinding circuit, both mechanical and operational, to resolve it deficiency. The SAG mill, in particular, was unable to achieve design tonnage initially and proved to be most troublesome. Complications occurred due to the hardness and variability of ore being processed, short component life, and a lifter /liner arrangement that had to be tailored to the particular circumstances at McLaughlin. IntroductionHomestake Mining Company's McLaughlin Mill, located in northern California, was designed to process a refractory gold ore at a rate of 3,000 tpd to render the ore amenable to cyanidation. Seven years transpired between discovery of the near-surface ore body in 1978 and the February, 1985 plant start-up. Development of the McLaughlin mill and open pit gold mine hinged on the use of autoclave technology to achieve design recoveries."

Jan 1, 1991

By Helge B. Wurst, Michael P. Cipold, Jan F. Bachmann, Claus C. Bachmann

"In washability, the objective is to establish the set of maximum possible separation performance criteria for a given mineral feed. The method of choice for this has been the conventional sink-float analysis. Time, cost and safety aspects of the sink-float method have prompted the search for a new approach for establishing separation performance criteria, especially as performance levels of separator plants can be maximized if reliable information based on an analysis of washability in conjunction with particle size distribution, elemental constituency becomes readily available. The new method to establish washability and associated performance information utilizes at least two measurement technologies concurrently: single energy x-ray transmission and image processing. For porous or very inhomogeneous materials the results can be refined further by using dual energy x-ray transmission and image processing. The value of the collected data increases considerably if the washability data were additionally available in time to be considered in the control of the process plant. The incorporation of an automated washability monitor gives near real-time data that would impinge positively on the profitability of the plant operation. The method was extensively tested with a range of sample with different densities, varying from 1 g/cm³ (coal) to 5 g/cm³ (iron ore).INTRODUCTIONWashability of minerals like coal and iron ore is expressed by a curve or graph showing the results of a series of float-and-sink tests. Several of these curves are drawn to illustrate different conditions or variables, usually on the same axes, thus presenting the information on one sheet of paper. Washability curves are essential not only for the design but also for the operation of preparation plants.In determining the washability analysis, particle density is the underlying feature of all washability curves. Conventionally, the particles are separated into density fractions by immersing them in fluids of a predetermined density followed by skimming of those particles that stay afloat. The particles remaining afloat thus have a density lower than that of the fluid they were subjected to. The particles that remained at the bottom of the fluid container thus had a higher density higher than that of the fluid. By progressively increasing, for example, the density of the fluid and immersing the remaining particles so as to be able to skim the next density fraction, the particles would be fractionated into density groups. The liquids used range from aqueous solutions to organic liquids to suspensions. Unfortunately the liquids used for this separation process are often toxic and expensive. It stands to reason that a new method of determining washability is sought."

Jan 1, 2016

The Bluebell mine of The Consolidated Mining and Smelting Company of Canada Limited extends under Kootenay lake, in southern British Columbia, and water control underground has always been a major problem. This paper gives a brief history of the operation, and then de-scribes the methods used by Cominco to keep the combination of lake seepage, ground water and thermal spring water under control. The pumping arrangements are de-scribed in considerable detail, with illustrations to show the various stages of development, and the power supply sys-tem is outlined.

Jan 1, 1966

By H. J. lgner

Hydraulic fills are widely used in the tabular, steeply dipping stopes of the South African gold and platinum mines as an integrated process within a daily cycle of drill and blast. There is therefore only a small time window in which to fill the geotextile bags used as primary fill containment, without the risk of loosing production. Consequently, mines tend to increase the flow rate to the stopes, although this compromises adequate drainage, consolidation and strength development during filling. Recent underground measurements inside the geotextile bag have revealed that at high rates of rise and at 25 degrees dip, the backfill can remobilise within a limited area inside the geotextile bag during filling. This sudden downward surge of backfill exerts, for only a few seconds, additional loading on the geotextile, its supporting mesh and the props. This unstable behaviour poses a serious threat as it can push props out of place, thereby damaging the geotextile bag and causing a mud slide in the stope. To reduce the risk of accidents, the phenomenon of sudden slumping was further investigated for various filling conditions in the laboratory. The results confirmed that the maximum pressures associated with the sudden slumping can be more than five times those experienced during steady-state consolidation. Based on this new insight, the current best practice for hydraulic backfilling was critically reviewed. A practical approach to implementing meaningful standards is presented to ensure safe operations in relation to the consistency of the backfill quality and the appropriate matching of geotextile characteristics with backfill properties.

May 1, 2007

By François Baillargeon

Two types of ore deposit provide the bulk of the world nickel production. They are the hypogene magmatic massive sulfide deposits and the supergene lateritic deposits. Platinum group elements (PGE) are also extracted from magmatic sulfide deposits. Recent sky-rocketing price of palladium has prompted the mineral industry to seek alternative resources. In such a manner has emerged the Lac-des-Iles type of target, a very low sulfide-bearing bulk tonnage type of deposit. Furthermore, unconventional (e.g. non-magmatic) types of deposit are now sought more intensively (Wilde et al., 2003). Considering both this trend of the PGE Industry, and that only a few magmatic deposits account significantly for the world nickel production, someone may wonder if a diversification of the hypogene nickel resources base would not be needed in the near future. Laterites are residual deposits developed on ultramafic rock under wet tropical climate. Are all ultramafic protoliths equal to generate high-grade lateritic deposit? Are some preweathering processes important to generate favourable ultramafic protoliths? The mineralogical heterogeneity of some ?dry? lateritic nickel deposits renders their ore beneficiation difficult. Is the type of nickel-bearing mineral found in the protolith a significant factor influencing the laterite heterogeneity? To contribute to answer all these questions, we have undertaken a research project on the nickel occurrences of the southern Quebec serpentinite belts. Why choosing this specific region for such a project? First because, due to continuous mining of asbestos ore since 1870, the serpentinite belts of this region are among the best exposed and studied in the world. Secondly, this region host a complete spectrum of nickel deposits that have been described before in the scientific literature. Furthermore, this region is slightly to moderately metamorphosed which make it perfectly suited to study the departure from magmatic nickeliferous paragenesis through various metamorphic conditions. As a matter of fact two orogenic events affected this region, the Taconian, in Ordovician time, and the Acadian during the Devonian. The magnitude and the timing of these dynamo-metamorphic events vary considerably through the region (Gauthier et al., 1994). These variations are now well constrained due to precise age dating.

May 1, 2003

By R. A. (Dick) McIvor

"It is important to ensure that the basic mine hoist plant design fundamentals are incorporated into any new mine hoist plant project before detailed design engineering is commenced. Some of the basic design fundamentals to be considered are: hoist rope fleet and flight angles for good hoist rope coiling, hoist rope harmonic frequency study to ensure that the hoist rope does not run at full speed at a rope resonance frequency, head frame and shaft clearance diagrams to establish the optimum positions for the loading and dumping of the shaft conveyances, access in the head frame and shaft collar for hoist rope and shaft conveyance installation and removal. Failure to consider the hoist plant fundamentals before detailed engineering commences will result in extra costs for hoist plant redesign or a significant increase in operating and maintenance costs for the mine due to increased hoist plant downtime to perform tasks and a lower mine operating efficiency. INTRODUCTION The mine hoisting plant is the most critical single line component in the operation of a shaft sinking operation or a permanent installation. Bad decisions in the design and selection of the hoist plant equipment can significantly add to the operating costs and up-time in the operation of the mine. Mine hoisting plant equipment installed costs represent approximately 5 to 8 percent of the capital cost of a new mine, yet price sometimes becomes the deciding factor for procuring the hoist plant components, sometimes selecting used equipment that may compromise the design and maintainability of the mine hoist plant. Mine downtime can cost upwards of $100,000 per hour and it will not take a very long time to eat up all the so-called savings on hoist plant equipment purchases. This paper will provide guidelines for the design, selection, installation and maintenance of mine hoist plant equipment with the objective to having the right mine hoist plant with the highest operational availability and best maintainability. PRELIMINARY DESIGN INFORMATION Before any engineering commences, the following information needs to be obtained to allow the preliminary sizing of the hoist plant equipment: • Shaft depth: The shaft depth will influence the hoist rope selection based on the material and personnel loads anticipated for the mine design. The shaft depth will also influence the maximum speed of the shaft conveyances. • Annual production: The desired annual production will influence the required payload sizing with allowances for maintenance and inspections of the hoist plant equipment."

Jan 1, 2019

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 A. Gakwaya, K. Ba, M. Guillot, J. Levesque

"In the aerospace industry, parts requiring tight dimensional tolerances and high mechanical properties are often produced by forging. This forming process allows for an optimal use of the material and can produce high quality parts at a reasonable cost. Thanks to CAD techniques, it is now easier to predict flow profiles and in-process defects occurrence as well as wear of the forging dies. However, in order to determine the properties of the forged part with computer simulation methods, a good material constitutive law is a prerequisite. This paper presents a virtual manufacturing process modeling for the closed die forging of a workpiece performed with Abaqus. The hot closed die forging is a regular process applied to manufacture metallic components used in aerospace industry. In this forming process, the material flow and final properties depend on the microstructure evolution during the process that is why it is important to include the microstructure effects in the material model. Based on the stress-strain data measured experimentally, the material parameters of the standard (classical) Johnson-Cook constitutive model and of a modified Johnson-Cook constitutive law including the microstructure effects have been determined. The obtained simulation results are compared with the experimental results for validation.INTRODUCTIONDue to their good physical and mechanical properties such as ductility, fatigue strength, corrosion resistance and rupture, aluminium alloys are often used in the aeronautic and the automobile industries. In this work, we present the forging of an Al-Zn-Mg-Cu alloy, a high strength aerospace alloy recognized for his good combination of physical and mechanical properties. The forging process is simulated in Abaqus Explicit using both the standard Johnson-Cook law (Johnson & Cook, 1983; Hor, 2011; Lin et al., 2012), and its modified version as proposed by Andrade et al., (1994). The Johnson-Cook law offers the advantage of considering the coupled effect of the plastic strain, the plastic strain rate, the temperature of forging and the hardening effect. However, it is a phenomenological model which does not account for the effect of the microstructure evolution. In this work, a modified Johnson-Cook model implemented in a user subroutine is used. It includes the effect of the dynamic recrystallization phenomenon during the hot deformation. The dynamic recrystallization has a noticeable influence on the microstructure and on the properties of the material. The term dynamic means that the process starts and acts during the deformation and this is different from the static mechanism of recrystallization which occurs during an annealing and after cold or hot deformation. Since properties of the alloy used in this work are not readily available in the literature then characterization tests have been done at various temperatures and strain rates, in order to determine the thermomechanical properties and the material behavior during the process of hot forming, more precisely during the hot forging process."

Jan 1, 2016