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By B. Krysa, J. Qiu

The zinc pressure leach plant at HBM&S's operations is now in its fifteenth year of operation. Current pressure leach operation is steady at a concentrate processing rate of around 26.5 tonnes per hour. A new cellhouse with a design capacity of 124,000 tonnes per annum and the capability of expansion of up to 154,000 tonnes per annum was commissioned in July 2001. The potential to expand the capacity of the pressure leach circuit and associated processes, as well as the purification circuit and casting plant, to meet the maximum capacity of the cellhouse has been investigated. This paper reviews current operation of the zinc plant, as well as the possibility of a capacity increase without major process modifications or major capital expenditures.

Jan 1, 2008

The theory and practice of sampling of particulate material have been the focus of a continued attention on the part of the mining industry worldwide for almost a century now, because of its critical importance at all phases of a mining project, from exploration (bulk sampling, assaying) to production (grade control) and marketing (quality control). A powerful, complete theory was put together by P. Oy (1968 to i982), but its applications to gold ores have met with limited success to date, due to the inadequacy of its sampling variance and minimum sample mass determination formulae to the challenging case of gold ores. This paper presents a research project completed at Inco Exploration and Technical Services Inc., using a geostatistical approach, to shed light on the results of P.Gy's theory, and adapt them to the case of particulate gold ores. After a reminder of Gy's formulae and a simplified demonstration of the generic form of Gy's and more traditional formulae, an empirical approach, based on sampling experiments from four gold deposits, shows how Gy's formulae must be corrected to adjust to the case of gold ores. The generality of the results formula is then substantiated with a geostatistical analysis of the problem. A parameterized formula results, and indications are given on how to fit its parameters to experimental data. Application guidelines and charts to fit any case and budget are presented, along with a detailed practical example.

Jan 1, 1991

By Ken G. Kress

Syphons can be a simple, reliable and proven alternative to otherwise more complex pumping systems or low level outlet works. In a simple form they consist of a pipeline constructed over the top of an embankment or high topographic feature, connecting a source pond to a receiving pond or channel (see Photograph 1). The syphon action is initiated by removing air from the pipeline (priming) using simple devices which can be purchased ?off the shelf?. Once primed, the syphon flow rate can be controlled or stopped using conventional gate, valve, orifice plate or other devices. Repriming is not required even if the flow is stopped, provided the syphon is not drained. A limiting factor in considering a syphon as a design option is the maximum lift (i.e., vertical distance from source pond level to summit of syphon) which is approximately 9 metres, or less, dependent on syphon pipe features and site conditions. Pipeline syphons can be quickly constructed from readily available materials including steel, polyethylene and PVC pipe. They are particularly well suited to many of the unique conditions often encountered at minesites. This paper identifies situations that can sometimes be best resolved using pipeline syphons. It provides basic principles for pipeline syphon design and includes case histories of their successful application.

May 1, 2001

By V. W. Shtenko, B. J. Ennis, P. H. Bridge

"The northeastern region of British Columbia contains large quantities of high-quality metallurgical coal. To market the coal, it was necessary to provide the required infrastructure which included rail access. This paper presents the role of the British Columbia Railway in the northeast coal development.In 1976, B.C. Railway undertook to study two main routes, one originating at Chetwynd and the other at Anzac, both located on the main line, north of Prince George. The routes studied are briefly described, detailing the methodology and engineering analysis carried out to permit the selection of a single route that would be the most cost effective, taking into consideration the construction, maintenance and operating costs. The operating parameters, track and grade standards, anticipated tonnage, construction costs and the final route selected are also presented.Pre-engineering analysis and studies of the route selected originating at Anzac, known as Tumbler Ridge Branch Line, and which commenced in 1977, were concluded in 1978. New mapping was developed to a scale of 1:2000 with good vertical and horizontal control. Based on the mapping data, terrain analysis, and designs developed, an estimate of construction costs and schedule of work was developed.Authority to proceed with the final design and construction was provided in December 1980, with the first shipment scheduled for December I, 1983. Final designs of all structures are discussed, including schedules, cost to completion, and control systems utilized. The decision to electrify the Tumbler Ridge Branch Line and related topics are discussed, with a brief description of train operations. The present status of the project is also presented."

Jan 1, 1983

By K. Feindel

The distribution of water in operating fuel cells must be carefully managed to optimize the performance, durability, and functionality of the system. For example, the ionic conductivity of polymer electrolyte membranes decreases as membrane hydration is reduced. Flooding at the cathode inhibits mass transport, and it can lead to failure of materials. Build up of liquid water in the gas flow channels of a fuel cell stack will create a non-uniform distribution of pressure drops across the individual cells. We will discuss the application of 1H NMR microscopy to investigate in situ the production and distribution of water throughout an operating H2/O2 polymer electrolyte membrane fuel cell. Polymer electrolyte direct methanol fuel cells posses high theoretical storage capacities as power systems for portable electronic devices. There are, however, two long-standing hurdles to development of practical methanol fuel cell systems. First, the electro oxidation of methanol at the anode of the fuel cell is poisoned by absorbed carbon monoxide, an intermediate in methanol electro oxidation. Second, methanol readily crosses over from the anode to the cathode of the fuel cell. This methanol crossover wastes fuel, and it poisons the electro reduction of oxygen at the cathode. We are investigating use of 2-propanol as an alternative to methanol as a fuel. 2-Propanol is less toxic than methanol, and it is less prone to crossover from the anode to the cathode. More significant, however, is that the electro oxidation of 2-propanol to acetone is faster than the electro oxidation of methanol because it avoids formation of adsorbed carbon monoxide. We will present active catalyst systems for the electro oxidation of 2¬propanol to acetone in fuel cells. We will also present methods to convert the resulting acetone back into 2-propanol, possibly leading towards rechargeable portable fuel cell systems.

Jan 1, 2005

By E. Mohammadi Zahrani

In this study, Mg-doped fluorapatite (Mg-FA) nanopowders were prepared through a sol-gel, technique and characterized. Designated degree of Mg2+ ions incorporation into the apatite structure was indicated by the x value in the general formula of (Ca10-xMgx (PO4)6F2), where x=0, 0.25, 0.5, 0.75, and 1. XRD, AAS, FTIR and TEM techniques were utilized to characterize the synthesized nanopowders. In vitro bioactivity of the powders was evaluated in simulated body fluid. Powders had a crystallite size less than 100 nm. It was concluded that Mg-substitution could alter bioactivity and dissolution behaviour of Mg-FA. These two parameters were proportional to magnesium content of the powders.

Jan 1, 2010

By E. G. Baltuch

Natural Ventilation in mining and metallurgical processing applications is key to proper operation function. There are number of ventilator designs available to a project team or design engineers, the selection of which will affect both the type of building structure required, project costs and design performance which is difficult to rectify or re-engineer once implemented. Research and applied results, such as that performed by Air-Therm Inc., demonstrates that computational fluid dynamic simulation allows for 5 dimensional observation, analysis and optimization at significantly lowered cost than previously possible. These results have been fully implemented on a number of mining and metallurgical applications and the company continues to study, optimize and innovate as new tools become available to provide the best possible engineered solutions for particular applications.

Aug 1, 2013

By J. S. Fox

"Besshi-type Cu-Zn (-Ag-A u ± Co) deposits are tabular, stratiform volcanogenic sulphide bodies which are usually associated with mafic volcanic rocks of oceanic or intra-plate geochemistry, but which can also be found locally with ultramafic volcanics or subvolcanic mafic intrusions. A thick sequence of continentally-derived clastic sediment usually encloses both the mafic volcanics and the ore. Besshi-type deposits form subaqueously, in epicratonic rifting environments, more-or-less proximally, and as a result of hydrothermal convection in their subjacent mafic volcanic - clastic sedimentary piles. They belong to a rift -related metallogenic spectrum that includes sediment-hosted and Cyprus-type base metal deposits, and may diller genetically from these mainly with respect to rate and degree of crustal extension. Modern analogues to these deposits are f ound in the submarine volcanogenic sinters of the Gulf of California rift system.The associated lithologies and tectonic selling of Besshi-type deposits clearly distinguish them from Kuroko-type ores. This difference also seems to be reflected in their lead isotopic character. For example, leads from Besshi-type deposits in the Sanbagawa belt of Japan and from the Blue Ridge belt of southeastern U.S.A. lie on extended anomalous lead lines and have lowslopes in 207Pb/204 Pb - 206Pb/ 204 Pbspace (Sato and Sasaki, 1980; Leriuray, 1982), wheras those from most Kurokotype mining districts exhibit only narrow isotopic ranges and lie near or on the orogene growth curve (e.g. , Franklin et a I., 1981). More over, where Besshi- and Kuroko-type deposits are found in the same orogene, the former often occur earlier in the tectonic cycle than the tatter (e.g., Japan, the Norwegian Caledonides, the southern Appalachians and south-central Finland).Besshi-type deposits are not confined to any particular part of the world, or to any geological epoch. Moreover, in many mineralized belts, Besshi-type deposits are the predominant volcanogenic ore type. On a world-wide scale, deposits of this type therefore constitute an important base metal resource."

Jan 1, 1984

By L. Jacobsson, J. E. Lindqvist

A series of laboratory tests were conducted to study stress-induced spalling on medium to coarse-grained granite specimens. The specimens made from cylinders had two manufactured notches on opposite sides aimed to represent the tangential loading around a circular opening. Specimens of three different sizes were tested with notch radii, 98.5, 225 and 375 mm, representing 197, 450 and 750 mm diameter holes, to study the effect of notch radius on the spalling initiation stress. The cracking was monitored by acoustic emission sampling. The fracture patterns were investigated visually on polished slabs and by microscopy on thin sections. The crack analysis describes how the cracks propagate in relation to the grain structure in the rock and to the macroscopic stress field.

Jan 1, 2015

By Ted J. Smith, Stephen E. Kesler

"Zonation patterns are welt developed in the mafic metavolcanic rocks that host epigenetic quartz-carbonate-gold vein mineralization at the Hollinger-McIntyre deposit. Carbonate alteration assemblages are strongly zoned about mineralization. Proceeding inward from background greenschist facies rocks to alteration envelopes enclosing individual veins, the following assemblages are observed:Assemblage I-quartz-albite-chlorite-epidote-actinolite-(calcite)Assemblage II-quartz-albite-chlorite-calcite-epidoteAssemblage III-quartz-ankerite-sericite-(chlorite-calcite)Assemblage IV-quartz-albite-ankerite-sericiteLithogeochemical zoning is equally well developed as variations in whole-rock abundances ofAs, Au, Ba, Rb, and Sb. As and Ba form the most useful zonation patterns, outlining individual ore zones as well as broader trends of mineralization.Gas chromatographic analyses of fluid inclusions in the quartz-carbonate veins indicate that the mineralizing fluid was an H20-C02 mixture. Locally, CH4-rich fluid inclusions are associated with graphitic and/or carbonaceous wallrocks. Fluid inclusions in ore-bearing veins have higher CO2 contents than those in non-ore veins. Extensive sampling and analyses of veins from the area surrounding the deposit reveals a well developed zonation of CO2 contents about the main zone of mineralization. Low CO2 levels (1-2 mole%) in veins are peripheral to the deposit and increase to over 12 mole% in mineralized zones.The observed zoning of the carbonate alteration assemblages is a result of the addition of CO2 to the wallrock, which is consistent with the zoning of CO2 in the fluid inclusions.The zoning patterns delineated in this study are useful in exploration both on a deposit scale and on the scale of individual ore zones."

Jan 1, 1985

By Bennett McLaughlin

The Penna Shaft is the deepest single?lift shaft in North America. AGNICO-EAGLE started sinking the Penna shaft in 1995 with a hoisting plant capable of hoisting 1 800 tonnes per day from a 2 240-metre deep shaft. Exploration success at depth lead to the replacement of the existing double drum hoist by another double drum hoist capable of hoisting 7 000 tonnes per day. The use of another double drum hoist, instead of a Blair Multi-Rope winder, to hoist 24,5-tonne skips was only made possible by lowering the safety factor. This paper describes recent experiences at Penna and in South Africa, and examines the possibility of extending the double drum hoisting system to a depth of three kilometres.

May 1, 2003

By C. R. van Staal, L. R. Fyffe, J. A. Winchester

"The geochemical characteristics of Early Paleozoic volcanic rocks are used to establish the following tectono-volcanic regimes in the northeastern mainland Appalachians: foreland continental rift volcanics; fore-arc ophiolites; island-arc volcanics; back-arc ophiolites; and back-arc ensialic volcanics. A Late Precambrian calc-alkaline magmatic arc bounds the Early Paleozoic volcanics to the southeast.The Precambrian calc-alkaline volcanics of the Caledonian Highlands, primitive Cambro-Ordovician oceanic-arc volcanics of the Eastern Townships, and within-plate Ordovician volcanics of the Miramichi Highlands can be related to a progressive change in mode of subduction from compressional Andean-type in the Late Proterozoic to extensional Western Pacific-type in the Early Paleozoic. The development of marginal oceanic basins in the Paleozoic created a more favourable environment for volcanogenic sulphide deposition, particularly in back-arc areas.The influence of tectonic setting is reflected in the distribution, size and metal ratios of the massive sulphide deposits associated with the volcanic rocks; deposits within intra-oceanic arcs in the Eastern Townships of Quebec average two million tonnes grading 2.2% Cu, 4.0% Zn, and 0.6% Pb, whereas those within a back-arc, ensialic rift near Bathurst, New Brunswick, average nine million tonnes grading 0.6% Cu, 5.4% Zn, and 2.2% Pb."

Jan 1, 1990

By Y. P. Malhotra, JE. C. Carter

"Syncrude's overburden removal requirement ranges from 20 million to 30 million bank cubic metres per year to meet tarsand demands for the production of 129,000 barrels of synthetic crude oil per day. The economic tar-sand lies beneath a variable thickness of overburden materials, composed of silts, clays, some sands of lacustrine origin, wind-deposited sand dunes, and out-wash sands and gravels.For the removal of overburden, Syncrude commissioned its own mobile equipment fleet in January 1981. This fleet consists of two Demag 241 hydraulic shovels, ten Titan 33-15B trucks and support equipment. Prior to this, all overburden removal was being carried out by contractors.This paper presents an overview of overburden removal at Syncrude, with particular reference to the performance of its own fleet.IntroductionThe Syncrude Tar Sands Plant was officially opened on September 15, 1978. After an expenditure of approximately $2.26 billion, the second and the largest commercial tarsands plant was on stream toward a permit production rate of 129,400 barrels of synthetic crude oil per day. The Syncrude Plant, a joint venture of six oil companies, the federal government and the Alberta government, is a major step forward toward the goal of Canadian energy self-sufficiency.The Mildred Lake operation of Syncrude Canada Ltd. Is located 40 km north of Fort McMurray and 480 km northeast of Edmonton in the Province o f Alberta.Synthetic crude oil leaving the plant is a blend of two-third s gas oil and one-third naphtha. The two streams combine in a pipeline and flow to Edmonton. The product takes six days to make the journey, arriving at four locations in the city Imperial's Strathcona Refinery, Gulf's Edmonton Refinery, the Interprovincial pipeline terminal and the Trans-Mountain pipeline terminal. Each Syncrude owner receives a share of oil equal; to its percentage of ownership in the project. At the present time, the oil is being utilized by Canadian refineries from Vancouver to Montreal."

Jan 1, 1983

By Derek H. C. Wilton

"The Cape Ray Fault Zone of southwestern Newfoundland contains two notable electrum/ base metal sulphide quartz vein lode occurrences hosted by two contrasting lithological units, viz. a graphite schist horizon and a granite. The two occurrences, although in proximity, are not in direct contact, but, based on geochronological, geochemical and isotopic evidence, they were apparently deposited from hydrothermal fluids generated as a vapour phase from the magmatic progenitor of the Windowglass Hill granite.This paper provides further evidence, from REE and background A u and Ag data, for the magmatic origin of the hydrothermal fluids. Wall rocks to the electrum-bearing quartz veins in both the schists and granite have experienced a LREE depletion probably due to leaching by Cl-bearing solutions. Gold and silver contents are typically low in all rock types but there is a slight elevation in gold concentrations in those units in contact with the Window glass Hill granite. The granite also has the relatively highest gold and silver contents of any unit in the region.IntroductionThis paper presents the evidence from rare earth element (REE) and gold/silver concentration data for the magmatic origin of hydrothermal fluids responsible for deposition of the Cape Ray electrum deposits of southwestern Newfoundland. The two deposits occur in the Cape Ray Fault Zone (Fig. I) within the Windsor Point Group and Window glass Hill granite. The larger occurrence is called the Main Shear Showing and consists of a deformed quartz vein horizon, which extends for - 6 km, within the late Devonian Windsor Point Group. This unit is an intermixed ignimbrite and mafic tuff sequence with associated schists (metasediments) and gabbros. The host rocks to the mineralized quartz veins are interleaved graphite, chlorite and sericite schists. Basal ignimbrites within the Windsor Point Group have been dated, by Rb/Sr isotopic methods, at 377 ±21 Ma (Wilton, 1983a). The basal ignimbrites also have enriched REE patterns, an elevated initial Sr ratio (0.709) and a peraluminous-siliceous nature which suggest they resulted from the partial melting of continental crust (Wilton, 1984)."

Jan 1, 1985

By B. J. Fryer, R. P. Taylor

"As a monitor of the processes involved in the formation of granitoid mineral deposits the coherent group behaviour of the rare earth elements (REE) actively reflects changing fluid characteristics. For example, in the porphyry environment, magmatic-hydrothermal fluids produce potassic alteration with strong enrichment in the light rare earth element s (LREE), reflecting their high pH, low fluid/rock ratios, and the dominant role of CI- complexing in metal (i.e. Cu, Au) transport. With increasing fluid/rock ratios and decreasing pH accompanying the progressive involvement of meteoric fluids (and the production of propylitic, argillic, and phyllic alteration) anionic species such as F - and CO, 2- become important in metal (e.g. Mo, W,) transport through complexing, and their activity in the hydro thermal fluids is illustrated by mobilization of the heavy rare earth elements (HREE).The relative involvement of CI- versus F - versus CO32- in metal transport in other granite-related systems can also be monitored through REE behaviour. Hence granitoid tin-tungsten mineralization and associated greisenization typically exhibit heavy rare earth enrichment and evidence the importance of F' and CO32- in metal transport. Similarly, heavy rare earth element enrichment in hydrothermal uranium deposits can be related to the transport of uranium as carbonate complexes. REE are widely accepted as powerful tools in the study of rock petrogenesis, but their use has been neglected in the investigation of mineral deposits. The recognition of the systematic variation of REE distributions in granitoid mineral deposits suggests that the application of REE geo chemistry, particularly when integrated with fluid inclusion and isotope studies, can provide (1) an effective method for identifying the physicochemical controls of metal transport and (2) a useful criterion for elucidating metal distribution."

Jan 1, 1983

By Eugene F. Mehr, Dennis C. Martin

"Development of the final slope for the 340 m (1200 ft) high hanging wall at Cassiar Mine precipitated an area of deep seated instability involving an estimated 17.6 million tonnes. The deformation mechanisms involved squeezing of soft deformable serpentinite rocks in the toe which caused planar sliding and graben toppling of the stronger sedimentary rocks in the middle and upper sections of the slope. Although movement rates up to 150mm/day were recorded, by understanding the controls on failure, the mine was able to install a suitable monitoring system and complete the open pit with only minor loss of the mineable ore. Accelerated mining was required in the last full year of operation. This paper describes the deformation behaviour, failure mechanisms and back analysis results for the failure. The monitoring systems and operational aspects related to the failure are also presented.IntroductionCassiar Mine is located in steep mountainous terrain in northern British Columbia approximately 1200 km north of Vancouver (Fig. I). During the final mining phase of the open pit, instability developed in the approximately 340 m high hanging wall (east wall) slope. A unique graben toppling mechanism was identified based on detailed assessment of slope monitoring data and visual observations. Comprehensive slope monitoring enabled mining to continue even though movement rates as high as 150 mm/day were being recorded. Three-dimensional limit equilibrium back analyses and numerical modelling have been used to assess the various controls on the slope movements and to understand the failure mechanism."

Jan 1, 1993

By John H. Walsh

"ForewordPart I of this paper, published in the March 1992 issue of the CIM Bulletin, surveyed the probable consequences of a limitation on the emissions of carbon dioxide to the atmosphere for the steel industry. What might be termed the conventional responses to this restriction open to the industry were also surveyed in that section. This section, Part II of the paper, explores a new option - the possibility for the joint production of iron and liquid fuels useful for transportation purposes. In this case, it is shown that it is important to minimize the production of carbon dioxide during the reduction stage to maximize the proportion of the reductant carbon embodied in the fuel. It is also advantageous to conserve hydrogen in the reduction step. In essence, the same carbon fulfills two purposes: it serves as a reductant and fuel for ironmaking and then as a constituent of a liquid fuel. If recovered plastics could be used in ironmaking, the same carbon could serve three useful purposes in turn. The conditions and limitations for the joint use of carbon in such 'cascading' processes are explored below. ABSTRACTIt is becoming increasingly probable that emissions of carbon dioxide from the fossil fuels will have to be reduced to deal with the threat of global warming. This issue is likely to be resolved one way or the other in the period 1995 to 2000 which does not leave much time to develop responsive options. In the intervening period, the policy of the Government of Canada is to stabilize emissions of greenhouse gases at their 1990 level by 2000, by encouraging greater efficiency in the use of energy. Should further reductions prove necessary, economic instruments would probably be employed but these would not be applied before a comprehensive international agreement is reached.There are three main themes in this paper: it is assumed that measures to control carbon dioxide emissions will in fact be necessary by the turn of the century; that there will be a rising need for liquid fuels to supply the world's steadily growing fleet of motor vehicles for many years to come, and that the future niche for Canada's industry in such a carbon-constrained world will be the operation of the energy-intensive industries with efficiency and environmental sensitivity.The steel industry, as a large user of both coal and energy in other forms, would be significantly affected by a need to reduce carbon dioxide emissions. This paper first examines what might be called the conventional responses open to the industry in such a situation and then explores a new possibility for making better use of carbon by the co-production of iron and liquid fuels."

Jan 1, 1992

By Roland Froidevaux

"The main object of ore reserve classification is to assess the reliability of an ore reserve estimate. Because traditional classification schemes fail to provide a means of calculating this reliability, the terms 'proven "" 'probable' and 'possible ' ore were introduced as an attempt to qualify it.Geostatistics, on its part, allows the quantification of the precision of any ore estimate and thus appears as an appropriate tool for ore reserve classification.However, the problem of fixing quantitative boundaries for ore classes remains. In order to be meaningful, ore class limits based on the degree of reliability should be customized to the commodity, and the type and size of the deposit. In addition, the precision of an ore estimate will be affected by the cut-off grade and the size of selective mining units.IntroductionPrimarily, ore reserve classification should be seen as a communication tool between the geologist and the mining engineer on one hand and the management and policy maker on the other. By classifying ore reserves, the geologist tries to answer the very fundamental question: ""What quantity of metal is there in the ground and how sure am I that it really exists?""The difficult y of quantifying the degree of reliability of reserves has led to the creation of a large suite of terms and definitions, with almost every mining company having its own set of definition standards. As lower-grade deposits are brought into production, the margin of tolerable error in estimates of the grade and tonnage is becoming much narrower. Consequently, the need for unequivocal definition of the reliability of ore reserves is increasingly acute. Most of the generally accepted systems of classification, however, describe the reliability of reserves in qualitative, rather than quantitative, terms."

Jan 1, 1982

By R. C. Beard

"Heap leaching, currently being applied in the treatment of low-grade ores in the south western United States, is shown to have potential for use in north western Ontario. The history and operation of the process are described, and cost comparisons are given.IntroductionHeap leaching is a simple, low-cost method of recovering gold from low-grade ore. Although it is not currently being used in Canada on a production scale, it is being used extensively, and successfully, in the southwestern United States as well as elsewhere in the world. Especially suited for large deposits of very low -grade ore, it also appears to be practical for use on small, high-grade deposits because it avoids the high capital costs of mills. Eveleth (1980) and others suggest that the capital and operating costs required for heap leaching are approximately 20% and 40% respectively of conventional milling methods.Northwestern Ontario is noted for its large number of undeveloped, small, high-grade gold deposits. Although there are a number o f larger and higher-grade deposits in the area as well, it is the relatively small undeveloped deposits which would benefit most from heap leaching, if it could be demonstrated to be a viable extraction method.To assess the significance of these small deposits, the Ontario Ministry of Natural Resources recently commissioned a consultants' study of the gold reserves in certain parts of northwestern Ontario. This report, titled ""Feasibility of Small-Scale Gold Mining in Northwestern Ontario"", by J.N. Neilson and R.C.E. Bray (1981, OGS Open File Report 5332), documents 106 known gold deposits having sufficient information to calculate gold reserves. A total of over 7.8 million tons having a weighted average grade of 0.19 oz of gold per ton were compiled in the proven, probable and possible categories, with an additional 8.2 million tons in the speculative category. Many of these deposits could be mined by open-pit methods."

Jan 1, 1983

By C. Kuehmann, B. Tufts

QuesTek Innovations has applied its Materials by Design® methodology to computationally design a new ultra high-strength corrosion resistant steel. Ferriurn® S53 eliminates the need for toxic cadmium coatings currently used on conventional steels in landing gear systems. S53 has the strength of 300M steel, and corrosion resistance similar to 15-5PH stainless steel. S53's corrosion resistance improves stress corrosion cracking resistance and reduces susceptibility to hydrogen embrittlement, improving component reliability and providing an opportunity for extended overhaul and repair intervals. Ultimate tensile stress is 1965 to 2000MPa. S53 was designed to be mechanically equivalent to 300M, with the key addition of intrinsic corrosion resistance. Alloy design, microstructural characterization, and mechanical properties are discussed herein.

Jan 1, 2006