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By Changping Hu, Keqin Tan

In 1937, the Metallurgical Department of the National Resources Committee established a copper refinery plant (predecessor of the Chongqing Smelter) in Changsha, Hunan Province, China. The blister copper produced by a local copper smelter was casted as anode for electrorefining. The plant, with a capacity of one ton of electrolytic copper per day, was designed and tested in 1937. At the trial production stage, a total of 9 tons of cathode copper was produced. The plant was formally put into operation in July 1938. In the same month, more than 20 tons of electrolytic copper with purity over 99.9%Cu was produced. This was the first batch of electrolytic copper produced in China. In 1939, China’s largest non-ferrous metal smelting plant, Fengtian Gold Mine Refining (predecessor of the Shenyang smelter) was completed and put into operation in Shenyang, mainly producing nonferrous metals such as gold and silver, as well as copper and lead. In 1939, the Kunming copper smelter (predecessor of Yunnan Smelter) was completed and put into operation. The plant equipment, imported from the United Kingdom, was designed to produce 1,200 tons of electrolytic copper annually. In 1943, Jiatong smelter (predecessor of the Shanghai Smelter) became the 4th domestic cathode copper producer. Since 1949, China has gradually established a large copper industry. These developments are discussed in this paper. Today, China operates nine out of the twenty largest copper refineries in the world. With a total capacity approaching 9 million tons of copper per year, China has the world’s largest copper refining capacity. INTRODUCTION China is a country with a long history of copper mining. The earliest smelter in China in recent times was the Shanghai Smelter, which was built in 1912. From then until 1949, China successively built Chongqing Smelter, Kunming Smelter and Shenyang Smelter. The world's first copper electrorefinery was the Pembrey refinery built in the UK in 1869 (Lu, 1999). However, it was not until 69 years later that the technology was spread to Changsha, China.

Jan 1, 2019

By Barbara Hendrickson

Outline ? Canadian Regulatory Update ? Turning the Corner: Background & Status ? Implications of U.S. Waxman-Markey bill for Canada ? Federal-provincial considerations ? Current certainties and uncertainties ?Turning the Corner? as Originally Proposed ? April 26, 2007 - the Canadian federal government announced Turning the Corner: An Action Plan to Reduce Greenhouse Gases and Air Pollution (?Turning the Corner?)

May 1, 2009

By Guoqiang Lan, Jun Song, Bin Ouyang

Rare-earth pyrochlores, commonly exhibiting anomalously low lattice thermal conductivities, are considered as promising topcoat materials for thermal barrier coatings. However the structural origin underlying their low thermal conductivities remain unclear. In the present study, we investigated the phonon properties of a group of RE pyrochlores, Ln2Zr2O7 (Ln = La, Nd, Sm, Gd) employing density functional theory and quasi harmonic approximation. Through the relaxation time approximation (RTA) with Debye model, the thermal conductivities of those RE pyrochlores were predicted, showing good agreement with experimental measurements. The low thermal conductivities of RE pyrochlores were shown to largely come from the interference between the low-lying optical branches and acoustic branches. The structural origin underlying the low-lying optical branches was then clarified.

Jan 1, 2015

By V. Dinesen

"Grinding is simply the function of reducing particles in size or creating new surface areas. This may be accomplished by many means but we will only concern ourselves with the continuous grinding process as performed in a revolving drum or mill, containing a grinding media. Such a mill consists essentially of a feed head, a cylindrical shell section and a discharge head. To prevent internal wear of these parts it is customary to attach replaceable linings over the wear areas. The specification and design of these mill liners is more important than generally conceded. As they reduce the effective internal volume of the mill, they will consequently affect the whole mill ·design and operation.A number of mill designs of various sizes are available for combined crushing and grinding of materials within a wide size range. For simplif1cahon purposes we will refer 1n particular to conditions relating to standard mill shapes having a length which is greater than the diameter. Such mills usually rotate at speeds between 60% to 85% of the critical speed and may, depending on the grinding media used, be classified as rod mills, ball mills and pebble mills.LINER MATERIALSA great variety of materials have been and are being used for mill linings. These include wood, ceramics and cements, rubber and plastic compounds, rolled and forged steels, cast steels and cast irons, both plain, alloyed and specially treated.The choice of a liner material depends on many factors. In both dry and \\.:et grinding, it may be necessary to consider product purity, colour, chemical reaction etc. but for our purpose we \viii refer to wet grinding operations as generally used within the mining industry."

Jan 1, 1972

By G. Bellefleur, K. Stevens, E. Adam, D. Synder, G. Perron, C. Müller

The Downhole Seismic Imaging consortium was initiated by the Geological Survey of Canada and three Canadian mining companies to assess the usefulness of borehole seismic techniques for the exploration of massive sulphide deposits within areas of steeply dipping stratigraphy. Field tests were conducted over two sub-economic massive sulphide deposits located in Norman West, Ontario, and Halfmile Lake, New Brunswick, using various shot configurations and a three-component borehole receiver array. The Norman West deposit, or structures associated with the deposit, produce detectable seismic reflections as far away as 1500 m. However, these reflections are difficult to distinguish from fault reflections and lithological contacts near the base of the Sudbury Igneous Complex. At Halfmile Lake, the rock properties are favourable for direct orebody detection. The Halfmile Lake deposit has a clear but relatively complex seismic signature on the downhole data, showing not only P-wave reflections, but also strong reflected S-waves and modeconverted waves. Such prominent S-waves and converted waves have not been recognized previously in borehole or surface seismic data acquired over massive sulphide deposits. These waves add complexity to the interpretation but provide additional imaging capabilities. Reflected S-waves and converted waves should be considered when designing seismic surveys for mineral exploration.

Jan 1, 2004

By G. Styles, K. Lye, R. Tenbergen, M. Mayhew

Requirements to produce a higher bulk concentrate grade have necessitated extensive use of on-stream analyser data and computer programming to obtain the targets set for Frood Stobie Mill as required by overall milling considerations.A brief history of milling process changes associated with the changes from a low grade (3% Ni) bulk concentrate in the sixties to a high (6 to 8.5%). Nil bulk concentrate currently will be presented.The heart of the presentation will be the computer control schemes for ""self optimisation"" of the distinct flotation sections in the plant within certain restraints to achieve targets set by the mill metallurgist.

Jan 1, 1985

By G. R. Rawsthorne

"The Con-Rycon mine is located on the north shore of Great Slave Lake in the Northwest Territories within the present city limits of Yellow-knife. Development work on the Con property started in 1936, resulting in a mine-mill complex which produced its first gold brick on September 5, 1938. Since that date 5,000,000 tons of ore have been mined yielding 3,000,000 ounces of gold. At present there are 220 employees at the mine.MineThe mine has 1.22 miles of vertical shaft, 41 miles of level development and 10 miles of inclined raises. There has been 1,000,000 feet of diamond drilling in search of ore. The temperature at the 4900 level (4400 feet below sea level) is 68 deg. F.The present mining method is cut and fill. The majority of the ore mined today passed through an internal winze before reaching the main shaft. The long haulage and double handling will be eliminated with the completion of a new shaft presently under construction to the 5800 level.MineralizationThe ore treated today is from the Campbell shear 1vhich is characterized by lenses and veinlets of coarse textured quartz containing some carbonate, sulphides and finely disseminated as well as visible gold. At the lower levels of the mine the arsenopyrite content in the ore is de-creasing with a~ increase in the levels of chalcopyrite and pyrrhotite."

Jan 1, 1974

By Balmer Neilly

In these days of arrested prosperity, when patience is tried and the future but dimly outlined, Canada's gold mining industry stands out as a beacon light shedding its rays of hope and confidence and demonstrating that there is still one product unaffected by Customs barriers and eagerly sought by all the people of the world. Some other forms of industry have hesitated and side-stepped. Some have cried for help, and in spite of public assistance, generously extended, they are still unable to demonstrate definitely their ability to resume the onward march. But gold mining has never hesitated. As an industry, it has bad an unique experience. When prices are high and conditions are generally referred to as prosperous, this industry is adversely affected. The cost of production goes up; profits are diminished; public sympathy is lacking; and, thrown upon its own resources, the industry tightens up its belt and throws its whole energy into an effort to improve operating conditions, and offset high prices by increased efficiency. When, in due course, depression follows inflation and prices ebb, the gold miner, through necessity, finds himself physically and mentally prepared to meet the situation.

Jan 1, 1932

By Peter Richards, Alexander Lewis-Gray, Mark Davies, Nicholas Katsikaros

"Gekko Systems developed the Gekko Resin Exchange Column (G-REX) in order to optimise the recovery of gold in complex leach-to-electrowinning processes, as an intermediate step using a highly gold-selective resin to isolate contaminant metals. The AuRIX®100 resin produced by Purolite is licensed exclusively to Gekko, with the G-REX column designed specifically for this resin (Lewis-Gray et al, 2015). Operational experience has been gained at the CGT Ballarat Gold Plant in near continuous operation since 2008, treating unclarified concentrate leach solution. The extension of the technology to higher throughputs and more complex chemistry is discussed.Aurix®100 ResinAuRIX®100 resin is a cross-linked polystyrene alkaline resin developed by Henkel (Virnig et al, 1996). The resin beads are off-white in colour, spherical, with a nominal size of 100% +600µm. This resin is highly selective for gold and silver over many metals, by way of extracting precious metal cyanide complexes from leach solutions with a pH less than 11.5. The higher end of the pH scale produces best selectivity according to the order of preference: Au > Ag > Hg > Zn > Ni > Cu > Co > Fe. Purolite produces the resin and Gekko Systems maintains licensing of AuRIX®100 resin for use in its G-REX column as part of its unique suite of gravity gold handling equipment.Significant cost savings over carbon-in-solution (CIS) systems are realised with AURIX®100 resin, of around 4% to 12% in capital savings and 27% to 40% in operating costs (Virnig et al, 2004). Allied to this is that AuRIX®100 resin is not susceptible to fouling, that is, the resin does not load with inorganic salts or organic compounds which would affect the loading and extraction of precious metals. To counter any potential for fouling by inorganic salts, in service a dilute acid wash is carried out periodically on the resin to unblock resin pores."

Jan 1, 2016

By J. Budac, E. Krause, C. L. Stewart, D. Wrana, S. W. Laundry

"As part of an over-all arsenic management strategy, Inco has developed a novel process that converts a by-product high moisture copper/arsenic sulphide precipitate into a crystalline copper arsenate suitable for the manufacture of wood preservation chemicals.The copper/arsenic sulphide precipitate is atmospherically leached with oxygen and sulphuric acid, producing a crude (blue) copper arsenate precipitate, elemental sulphur, and a copper and nickel containing solution. The blue copper arsenate is dissolved with sulphuric acid, the molar Cu/As ratio is raised to 2, and a crystalline copper arsenate (olivenite) is precipitated by the addition of sodium carbonate. Dissolved copper is recovered using metallic nickel (or matte) and elemental sulphur, to produce a low-moisture (low-arsenic) precipitate suitable for standard nickel-copper processing.The process was successfully piloted at Inco's Manitoba Division between September 1990 and June 1991. The copper arsenate product typically analyzed 43% Cu and 25% As, and the moisture content was about 10%."

Jan 1, 1995

By Zorigtkhuu Davaanyam, Bern Klein, Stefan Nadolski, Amit Kumar

"The High Pressure Grinding Rolls (HPGR) is a relatively new comminution technology that has been shown to be more energy efficient compared to semi-autogeneous (SAG) mills. Full and fair consideration cannot be given to HPGR-based comminution circuits in early stage projects, because presently pilot scale testing is required for assessing and sizing; pilot scale testing requires bulk samples weighing more than one tonne. A CAMIRO research program was conducted at the University of British Columbia to develop bench scale tests that would reduce the quantity of sample required to assess HPGR.Three test procedures were developed.1. The Direct Calibration Methodology calibrates piston press test results to pilot scale test results such that piston press tests can then be used to determine the energy–size reduction relationship for a range of ore types.2. The Database Calibrated Methodology, which is similar to the Direct Calibration Methodology except that it calibrates piston press tests against a database of pilot scale and piston press tests.3. The Semi-Mechanistic Methodology was developed to use piston press test results as an input for an HPGR based energy-size reduction performance model.Through utilization of these methodologies, the energy–size reduction performance of an HPGR can be predicted with minimal sample requirement. In addition, piston press testing is far more cost effective, faster, and accessible than pilot-scale HPGR testing.IntroductionOne could argue that in the future, decisions regarding selection of comminution circuits will be made primarily on the basis of energy consumption. The following facts and predictions support the argument:"

Jan 1, 2015

"Automatic flotation control in varying degrees of sophistication is practiced at a number of concentrators throughout the world. Practically, the variable conditions in the flotation circuit and the difficulty in maintaining accurate instrumentation information all add to the complexity of automatic control.Further development at the Kidd Creek concentrator has resulted in a 3075 mtpd copper flotation circuit capable of running twenty-four hours a day under the direct control of an optimizing supervisory computer.Three main streams, continuously monitored by an XRF analyser, supply circuit information to the optimizing computer. Circuit efficiency calculations (from smelter contract terms) and target setpoints allow the computer to determine the economic optimum direction to move the circuit based on the grade/recovery relationship. Circuit manipulation is accomplished by precise pumping of collector and frother reaqents together with accurate control of flotation bank pulp levels. The former uses computer controlled diaphragm pumps and the latter is achieved by control loops utilizing a float type level transmitter, variable position dart plugs and a process computer working to setpoints determined by the optimizing computer.The development of a fully automated flotation circuit is by no means complete, but increased knowledge and major hardware improvements have allowed its progression to a higher level of sophistication."

Jan 1, 1983

By R. Patrick

As a unique South African organisation, CSIR: Division of Mining Technology (Miningtek) strives to support the mining industry by improving health, safety and productivity through developing, adapting and transferring technology. Considerable effort is currently directed towards the development of potential non-explosive mining methods with the potential to allow continuous mining in narrow reef conditions. Besides improving productivity, continuous mining results in concentrated mining which has a significant impact on reducing infrastructural costs. Impact Ripping and Water Pulse Rock Breaking have been tried on gold mines, whereas Activation, Mini-Disc? cutting and the Plasma Holemaker are currently being tested on platinum mines. The organisation?s many years of experience in novel rockbreaking, together with its world-wide collaborator network, has placed it in a unique position to assist the mining industry and manufacturers in developing and/or adapting existing technologies for application underground. Currently a range of technologies are being investigated, which have reached different stages of maturity. The main technologies under investigation are; - Impact ripper system - Water pulse rock breaking - Activated undercutting rollers - Mini disc cutters - Electric rock breaking

Oct 1, 2001

By Jose R. Hernandez-Aguilar, Chris J. Martin, Rob Thorpe

"This study presents an approach to establishing relationships between metallurgical performance and the characteristics of the bubble population (gas dispersion) inside flotation cells. Bubble size Db, superficial gas velocity Jg, and bubble surface area flux Sb (Sb = 6Jg/Db) measurements were obtained along with metallurgical samples in full-size equipment processing different ore types. The gas dispersion was manipulated by changing the operating conditions of the cells (gas flowrate and frother type) and the metallurgical performance (grade-recovery) was determined. In two cases, the Sb had a strong relationship with grade and recovery, hence, Sb could be used as practical operating parameter. In another case, Sb did not correlate with recovery. The reasons were attributed to creating small bubbles using frothers with desired anti-coalescence properties. This illustrated that bubble size was the key parameter for metallurgy rather than Sb.INTRODUCTIONUnravelling the mechanisms that govern the relationships between metallurgical performance and the characteristics of the bubble population (gas dispersion) inside a flotation cell remains a major challenge. Information on this subject is scarce in the literature, particularly, plant-scale data. The report of Jameson and Allum (1984) appears to be the first gas dispersion study conducted in industrial (mechanical) cells. To introduce concepts, some aspects of their work are reviewed here.The prime motivation of that study was to establish whether any particular cell design (among 44 cells surveyed) could produce very small bubbles (< 0.1 mm), which laboratory research suggested would increase the recovery of fine particles. Although one of the outcomes was that the (examined) cells did not seem to produce such small bubbles (Sauter mean1 D32 ˜ 0.9 mm), the analysis highlighted the importance of including other factors. Jameson and Allum indicated that, besides bubble size (Db), other characteristics of the bubble dispersion should be considered, namely: gas holdup ?g – the fraction of cell volume occupied by bubbles, superficial gas velocity Jg – is the gas flowrate divided by the cross-sectional area of the cell and, bubble surface area flux Sb – the rate of production of (new) bubble surface area (m2/s) per m2 of cell cross-sectional area. It should be noted that, whereas Jg, ?g and Db can be measured directly, the Sb is derived: Sb = 6Jg/Db, where Db is usually substituted by the Sauter mean diameter (D32)."

Jan 1, 2006

By Neil R. Burns, Michael Doggett

Abstract - The Nanisivik mine offers a unique opportunity to examine the economics of a mining scenario from its original feasibility study through to closure. In the early 1970s, the Strathcona Sound project (exploration around the Nanisivik mine) had advanced to the point where a significant mineralized body had been defined and a feasibility study was initiated. The study supported development of the Nanisivik mine, with government investment in regional infrastructure, and the mine was constructed and operated for 26 years. Many elements of the feasibility study were difficult to estimate because the project was unique in its high Arctic setting. As a result, many differences were found when comparing the actual mining data to the feasibility study. The majority of these differences were the result of an actual mine life of 26 years instead of the planned 12.5 years. Most of the mining costs were higher than estimated and production occurred at a much higher extraction rate than planned. On a constant dollar basis, the metal prices were, on average, below the feasibility estimates. For the most part, these differences balanced out, with the actual mining being only slightly more profitable than anticipated in the feasibility study.

Jan 1, 2004

By P. J. Mehrfert

"Recovery of mineralized coarse particles is notoriously low in conventional concentrators that treat copper porphyry ores. The application of coarse particle flotation techniques has the potential to achieve comparable metallurgical performance at significantly coarser primary grind sizings. ALS Metallurgy has been conducting both internal research and commercial test programs to investigate the potential of Eriez HydroFloatTM technology on copper sulphide ores. Test data indicates that significant improvements in the recovery of copper sulphide bearing particles between 200µm to 850µm can be achieved using Hydrofloat technology compared to conventional flotation techniques. This paper summarizes the results from a selection of test programs that includes recovery by size data from both conventional flotation and HydroFloatTM tests. An explanation of the apparatus and test procedure will be given. Mineralogical analyses of the test products and characteristics that limit metallurgical performance will be discussed.Description of Apparatus and Test ProtocolThe HydroFloatTM laboratory cell is a clear plastic column with an internal diameter of 14 cm. Water and air are introduced to the cell through a circular manifold located in the lower portion of the cell. The cell has a conical bottom which directs slurry to a pinch valve that controls the discharge of tailings. Feed solids are introduced to the upper portion of the cell in slurry form. The cell is operated in a manner such that the manifold water creates a teeter bed zone of suspended solids in the middle portion of the cell. Tailings exit the bottom of the cell at a high pulp density, and most of the introduced water overflows the top of the column and is collected in a launder. Particles with a hydrophobic surface may attach to air bubbles that percolate through the teeter bed, rendering them sufficiently buoyant to be transported to the overflow launder.Three significant features of this arrangement enhance the potential to recover coarse, low grade particles by flotation techniques. Firstly, the hindered settling conditions created by the rising column of water allow coarse particles to become buoyant once attached to a modest sized air bubble. Secondly, the flow conditions within the cell are relatively quiescent compared to a conventional flotation cell that utilizes an agitator. This allows particles that have limited hydrophobic portions of their surface, due to a low content of exposed sulphide mineral, to maintain a somewhat fragile attachment to air bubbles long enough for successful recovery to the overflow. Finally, the absence of a froth phase at the top of the cell allows particles attached to air bubbles to immediately exit the vessel, reducing the potential to drop back into the pulp phase as bubbles burst or coalesce."

Jan 1, 2017

By Tom C. Palangio

The mining industry has come to rely on imaging devices to monitor and record all kinds of activities. We use them to measure, improve the process, ensure security, increase production and automate machinery. Cameras can be installed in locations most people wouldn?t want to live and be our ?eyes? to record the events at that location. This paper discusses digital imaging, the equipment, methods, techniques and information that can be learned from digital devices used in mining operations. The guy who said ?a picture is worth a thousand words? probably understated it. Images are the perfect way to document conditions before, after and even during mining activities. Today?s wide choice of cameras, camcorders and other digital devices allow us to record most activities and events. The technology is advancing at a high rate. Digital cameras and camcorders are marvels of technology with high resolution optics, compact size, automatic time and date stamp, great battery life, shutters to freeze motion and computers to auto focus and eliminate jitter (image stabilization). Add to this the economical price and ease of use and everyone in this industry should be aware of the possibilities.

Oct 1, 2010

By A. Ouellette, E. Nilsson

"Preventative maintenance is a burden for equipment users but a demand from the machine suppliers to ensure performance. Machine availability depends on preventative maintenance being followed.Mining equipment is becoming more and more sophisticated and productive, yet less and less time is available for preventative maintenance. Manufacturers invest in reducing costs, simplifying operating requirements, and lowering maintenance requirements, but it is the users who must invest more heavily in the advanced maintenance systems to keep the units operating.IntroductionPreventative maintenance has been, and still is a key factor in avoiding disturbances in production due to equipment downtime. Manufacturers ask for it in extensive maintenance schedules, check lists, programs, etc. often with a ""threat"" that, if not performed, the machine guarantee will not be valid. Modern mining and construction machinery has become sophisticated, like all other machinery, with elaborate hydraulic, electric and electronic systems and computerized controllers. Maintenance organizations within the mining industry have grown to heavy cost centres just to keep up the availability of the equipment.It is difficult for machine manufacturers to have maintenance programs that suit every user. International suppliers have to deal with different cultures, education levels, environments, organizations, etc. Maintenance programs recommended by manufacturers often do not meet some user&apos;s needs while they are ""overkilling"" to others. Preventative maintenance schemes recommendations of what to do, in what frequency, etc.) usually fit mechanical components in the equipment, e.g. wear measurements, crack indications, lubrication, oil changes, etc. But how does one perform preventative maintenance on huge hydraulic systems, electrical and electronic systems and computers? Failures in these systems usually occur without any warning and are more or less impossible to predict. Another difficulty in creating effective preventative maintenance programs for these kinds of systems is the relatively low volume of mining and construction equipment that is produced per year. For example, although Atlas Copco is one of the largest manufacturers in the world of underground blast hole drilling machines, the company still does not produce more than a few hundred drilling jumbos per year. These are made in more than 10 different models, with different systems and components, and very often are custom adapted to the end user&apos;s requirements."

Jan 1, 1992

By A. M. Krzanowski, T. S. Golosinski

"This paper presents results of a study undertaken to determinethe feasibility of mining plains overburdens with bucket wheel excavators. Based on extensive geotechnical testing of overburdens under study, the relations between material geotechnical properties and its cuttability were defined. The properties with the highest correlations to the cuttability werethen used to develop the material diggability classification. This classification may be used for identification of overburdens and coals mineable by bucket wheel excavators.IntroductionLow cost of mining and high productivity can be achieved when mining unconsolidated soils and soft rocks with bucket wheel excavators. As a result this mining equipment will likely be introduced into plains coal mines. At present there are plans to use a bucketwheel excavator (BWE) in at least one mine by the end of this decade. Unfortunately, the performance of a BWE deteriorates rapidly with the increasing strength of mined material. To avoid costly misapplication, material diggability must be defined in advance of an application (i.e. the force required at the cutting edges of BWE buckets must be quantified). Correct definition of material diggability permits reliable selection of a BWE, or may indicate unsuitability of this equipment for a particular application.The reported studyu i was undertaken to investigate the diggability of typical prairie overburdens and thus provide a guidance for likely future applications of bucketwheel equipment. Investigations concentrated on the parts of overburden most likely to create problems for a BWE mining. These are defined in Table 1. At present, thin layers of the two investigated materials (samples K and L) are mined by a BWE in an oil sand mine, after being loosened by blasting."

Jan 1, 1987

By J. P. Landriault, F. W. Harrison

"Zinc-iron alloy coatings can be produced by either thermally alloying hot-dipped galvanized steel or by electro deposition. Stelco Inc. produces a thermally alloyed Zn-Fe alloy-coated steel, which is mechanically wiped to remove free zinc.A more extensive use of Zn-Fe alloy-coated steel has been predicted for unexposed autobody and structural part applications, since this material is characterized by good spot weldability and formability, and provides superior corrosion resistance under automotive primers.This investigation has examined the coating composition, corrosion resistance, spot weldability and formability of Stelco&apos;s Zn-Fe alloy-coated steel and found its properties to be similar to those of Zn-Fe alloy-coated steel produced by post coating annealing.IntroductionRecently, there has been increased automotive interest in galvanneal, which is characterized by good spot weldability, good paintabilityt and good corrosion resistance when primed. Stelco produces a thermally alloyed zinc-iron coated sheet product similar to galvanneal. However, this product is produced by mechanically wiping the free zinc from the surface of hotdip galvanize to expose the underlying zinc-iron alloy.The surface of Stelco zinc-iron alloy-coated sheet is matte gray and has longitudinal streaks which result from contact with Kevlar wipers during production (Fig. I). This paper describes the coating composition, corrosion resistance, weldability, formability and surface appearance of Stelco zinc iron alloy coatings and, wherever possible, compares these properties to those of galvanneal."

Jan 1, 1987