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By Józef Czernecki

The Polish copper concentrates are characterised by low content of sulphur and iron. At KGHM Polska Miedz S.A. two copper production technologies are in use. The shaft furnace process is used at the Legnica Copper Smelter and the Glogów I Copper Smelter. A single-stage direct to blister Outokumpu flash smelting process is used at the- Glogów II Copper Smelter. Melting copper concentrates in the shaft furnaces is carried out in a reducing atmosphere and the product obtained is a matte. Instead, a result of melting copper concentrates by an oxidising flash process blister copper of a quality similar to that of converter copper is obtained. The annual copper production at KGHM Polska Miedz S.A. exceeds 450,000 tons. Another important metal is silver produced from slimes from copper electrolysis (about 1000 t/y). Moreover, such metals as Pb, Ni, Se, As, Au and other precious metals, including Pt and Pd, are recovered from various semiproducts. This paper presents technological flow sheet of the copper production in plants using the shaft furnaces and in another plant in which a single-state flash process is applied. Characteristics of products, methods of their utilisation, main parameters of particular technological operations, and advantages and shortcomings of the solution applied are presented. There are also discussed: the natural environment protection as well as directions of the KGHM Polska Miedz S.A. plants modernisation.

Jan 1, 1999

By Xiyun Yang, Hui Xu, Xichang Shi, Xiang Xiao

"Rod-like magnetite particles were prepared by precipitation of iron salts with urea under the induction of magnetic field. Temperature and initial Fe3+/Fe2+ ratio have a significant effect on the composition of the product. Magnetite particles change from spherical into rod shape in the presence of a 0.35 T magnetic field, The addition of a small amount of spherical seeds increases the rod-like magnetite particles yield. The seeds are prepared by aging ferrous and ferric solution with sodium hydroxide as precipitator. The aspect ratio of the rod is controlled by varying the volume ratio of seed to iron salt.IntroductionMagnetite, an important member of magnetic materials, has attracted a lot of attentions for its super magnetic properties. The rod-like magnetite particles have high anisotropy and coercive force as well as super magnetic properties compared to other shapes, and are widely used as high magnetic density media, magnetic devices and microwave materials [1-4]. Recent studies have found that magnetic field can direct magnetite growing along easy magnetization axis to get one-dimension particles [5-6]. Chen et al. [7] synthesized single crystalline nanorod magnetite under magnetic field. Wang et al. [8] discovered that magnetite grew along easy-magnetization directions under 0.35T magnetic field. Vereda et al. [9-1 O] found that magnetic field had a dramatic effect on the morphology, inducing the aggregates to line along one direction to form rodlike particles.At present, most of the synthesis methods reported in the literature result in a low yield of rod particles and the aspect ratio are difficult to control. Recently, we developed a seed-mediated growth approach to making rod-like particles in an aqueous solution. The spherical magnetite generated by oxidation serves as a seed. These seeds are then added to a solution containing iron salt and urea, and provide nucleation sites for magnetite rod growth."

Jan 1, 2011

By Jorge Alberto Soares Tenório, Victor Bridi Telles, Denise Crocce Romano Espinosa, Felipe Fardin Grillo, Vicente de Paulo Ferreira Marques Sobrinho, José Roberto de Oliveira

"This research aims to study the process of incorporation of the metal iron in electric arc furnace dust (EAFD), from a steel mill producing long steel by liquid iron in addition to the changing temperature of 1400 degree Celsius altering experimental conditions such as how to add the EAFD (as received and in the form of briquettes), the percentage of EAFD to be added (10, 20 and 30% of initial weight of sample pig iron) and the time of withdrawal of the sample of pig iron and slag (30 minutes after the addition of EAFD). Previously, the EAFD will be characterized using the following techniques: chemical analysis, particle size analysis, X-ray diffraction, scanning electron microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) microanalysis. After characterization, the eletric arc furnace dust to be added to the bath of liquid iron, will be divided into 2 types: the first order of addition will be in the form ""as received"" from the plant and the second is through the agglomeration of EAFD in the form of briquettes. The achievement of fusion experiments in laboratory scale, will take place in a vertical tubular furnace with temperature control. The fusion experiments to assess the incorporation of the metal iron will use graphite crucibles. A flow of inert gas (argon) will be maintained inside the furnace during the experiments. It is expected that the results obtained at the end of the research allow the evaluation of the iron metal incorporation of eletric arc furnace dust in hot metal bath.IntroductionThe steel industry generates a variety of solid wastes, liquid effluents and gaseous emissions at various stages of processing. The electric furnace dust (EAFD), generated in electric arc furnaces, represents a major problem for their content of chemical elements such as zinc, iron, chromium, cadmium, among others, issued to the atmosphere during the manufacture of steel[1]."

Jan 1, 2012

By Graham J. C. Carpenter, Marc Charest, Jason Lo

"The method of producing magnesium-based composites with silicon carbide (SiC) particulates embedded in the matrix of magnesium AZ9I D alloy by the squeeze-casting technique are described. This method involves the fabrication of a SiC particulate preform and the subsequent squeezing of molten magnesium into the preform. In this study, alumina, aluminum phosphate and a proprietary binder were used for the fabrication of SiC particulate preforms. The procedures employed in the fabrication of SiC! AZ9ID composites are presented, together with the results of characterization of the composites using optical and transmission electron microscopy. Special attention is given to the reaction products in the bulk alloy and at the interfaces between SiC particles and the AZ9ID matrix alloy.1. IntroductionInterfacial, microstructural and metallurgical characteristics play an important role in determining the mechanical properties of a composite. In theory, reinforcing magnesium with SiC particulates should provide an improvement in strength and modulus of the composite over the unreinforced counterpart. However, many factors resulting from the fabrication process can cause degradation rather than improvements to the mechanical properties. In particular, the interfacial characteristics are known to critically influence the properties of composites [1]. Before evaluating the mechanical properties of a composite, it is always useful to examine the microstructure, which is closely related to the mechanical behavior. This helps to reduce the labor-intensive steps of sample preparation for mechanical property evaluation, which can be particularly difficult as a result of the high hardness of composite materials, as well as providing a wealth of information on the microstructural and interfacial characteristics, particularly the reaction products caused by processing. This information is also pertinent in understanding the factors governing the mechanical properties of the composites.There are many factors which determine the nature of the interfacial characteristics of a SiClMg composites. Qualitative estimations of the interfacial bonding have been performed based on thermodynamics, electronic and electrostatic concepts. In addition, the kinetic conditions during the fabrication play an important role. From an interfacial energy standpoint, the driving force for the formation of a metal/ceramic interface is the decrease in free energy that occurs when intimate contact is established between metal and ceramic surfaces. The simple representation of the energy change per unit area of interface formed (~G) is given by Dupre equation [2]:"

Jan 1, 1996

By Yanlong Li, Lifeng Zhang, Ying Ren

In this work, a multiphase mathematical model for the fluid flow in argon-stirred steel ladles was established and validated by experimental measurement of wood's metal. Alloy dispersion in the molten steel was calculated. The melting and mixing of alloy was faster with smaller size of the alloy particles, larger superheat and bigger slip velocity. The current mixing time is approximately 300 s with 30 mm alloy diameter and 91.5 K superheat.

Jan 1, 2014

By Flávia Paulucci Cianga Silvas, Otávio da Fonseca Martins Gomes, Viviane Tavares de Moraes, Denise Crocce Romano Espinosa, Jorge Alberto Soares Tenorio, Guilherme Apostólico Bortolini, Stoyan Gaydardzhiev

"Printed circuit boards (PCB) are particularly problematic to recycle because of the heterogeneous mix of organic materials, metals, and glass fiber. PCBs are found in almost every electroelectronic equipment and their recycling process involves a pre-treatment to separate the products which contain targeted metals. In this work, a physical processing involving sequential shredding and hanuner milling were used to obtain a comminuted sample from scrap printers PCBs. The thus prepared sample was analyzed for particle size distribution and by optical microscopy as well was subjected to pyrolysis, leachabilty and chemical composition determination by XRF. The metals concentration was determined by ICP and AAS. The PCBs have been also analyzed by SEM-EDS (micro-analysis and X-ray mapping). The results show that the studied PCBs are lead free, multilayer with 4 copper layers, have 45% of metals and the copper is present in significantly higher concentration than the rest of the metals.IntroductionThe global generation of e-waste (electrical and electronic equipment waste - WEEEs) grows at a rate of about 40 millions of tons per year [ l].Among this e-waste there are PCBs that are present in almost all electronic equipment. Their composition is heterogeneous and varies according to several factors, including: kind of EEE, when and where it was produced, fabrication technology [2], etc. In printers, the PCBs represent about 6.6- 8 wt.% [3].The PCBs treatment may include physical, pyrometallurgical, hydrometallurgical, ectrometallurgical and more recently bio-hydrometallurgical process. Normally there is a combination between these processes [2, 4, 5, 6, 7, 8, 9, 10].The diversity between the different PCBs composition complicates the recycling process since the composition of metal and others materials can vary according to the models. So characterization is an indispensable step before any processing of PCB to begin. Owing to the above said, the main goal of this work has been set to characterize representative samples of PCBs from printers through physical, chemical and microstructural analyses."

Jan 1, 2014

By N. J. Tannyan

Laboratory bath smelting tests were conducted to determine the feasibility of smelting nickel- copper concentrate directly to a low iron matte in one step. Concentrate, air/oxygen and a silica flux were fed to a matte-slag bath kept in MgO crucibles at I 300°C. Various oxygen enrichments and smelting rates were used to maintain 0.5 to 2 wt% iron in the product matte. The slag losses are comparable to those obtained under similar industrial conditions. Due to the highly oxidizing conditions required to produce mattes with low iron contents, it is not recommended to target iron contents below about 2% in the matte. The specific bath smelting rates were equal to or higher than those in various industrial bath smelting processes.

Jan 1, 2003

By C. H. Tsau

The intermetallic compounds of Ni-25Al-xFe, x is 20-40 at.%, were prepared by arc melting and drop casting into ingots, and were rapidly solidified into ribbons by melt spinning. The microstructure evolution of these alloys with varied Fe content were examined by the x-ray diffraction, optical microscope, scanning electron microscopy and transmission electron microscopy. The results reveal that two phases, {y'} and {B} phases, are existing in the alloys with low Fe content, and the microstructure changes from the mixture of y' and {B} phases to a single 0' phase when the Fe-content reaches to 40 at.%. Also, the formation of y' phase will be suppressed by rapidly solidified process. For annealing both of the melt-spun and the cast specimens, a disorder 0 phase was revealed in both of the ribbon and the cast ingot of Ni-Al-Fe alloys with higher Fe content. In addition, increasing the increment of iron which substituting nickel in this alloys results in increasing the lattice parameter of both {y'} and{B} phases.

Jan 1, 1992

By William A. Hockings

Methods for the measurement of liberation of finely ground iron ores are described. The general method consists of separating a sample of the ground ore into a number of size fractions, followed by measuring the liberation of each fraction. The size separation has been done using electro-formed screens of 20-, 10-and 5-micrometer apertures, and also by air elutriation. Liberation (i.e., the distribution of compositions of individual particles) has been measured by optical microscopy. A computer pro-gram was used to adjust the raw count data so that it agrees with the chemical analyses of the size fractions. Various ways of presenting the results are given, and Some applications of the results to flotation processing are discussed.

Jan 1, 1981

By Zhihe Dou, Yan Li, Qiuyue Zhao, Guozhi Lv, Yan Liu, Hongliang Zhao

"Abstract: How to reduce carbon dioxide emissions has become a vexing problem, meanwhile, there exist high energy consumption and low efficiency problems in the existing CO2 capture and storage technologies. For CO2 comprehensive Utilization, this paper researches a new technology of absorbing the CO2 emission with high alkaline calcium or high alkaline wastewater sludge mineralization of calcium and invent a core device for multi-level jet carbonation. The industrial test has been carried out in China Xinyu slag Engineering Co., Ltd. The wastewater flow is 150m3/h in the pilot scale. The prepared calcium carbonate has a whiteness greater than 90%, particle size less than 150nm. The mineralization of aluminum exhaust with waste carbide indicates that the CO2 absorption rate is greater than 99.0%, CO2 concentration in the exhaust gas is lower than 0.08%, the purity of mineralized calcium carbonate is greater than 99.0% and particle size is less than 100 nm.InstructionAccording to the statistic data from IEA (2009), the carbon dioxide discharge from fossil fuel consumption in China has exceeded it in the US by the year of 2007, China, has become the largest emitter of carbon dioxide all over the world. Meanwhile, the economic scale is still on an increasing trend in the next 50-100 years, leading to a continuous increment in carbon dioxide discharge. According to the international energy agency forecasts, the energy-relative CO2 discharge in China will rise to 11,615 million tons, 91.3% higher than it in 2007. In the year of 2012, the CO2 gross discharge has reached 10,000 million tons, obviously higher than the predicted value. It is a tremendous task to reduce the emission. Non-ferrous metals industry is one of the largest emitters of carbon dioxide among the industrial circle, the whole industry might discharge a huge amount of carbon dioxide (over 600 million tons), in which the electrolytic aluminum industry is the largest energy consuming industry and CO2 emitter. At present, the CO2 discharge has focused by the whole world due to the environmental problems it causes; meanwhile, supplement of new carbon source is needed due to the exhausting oil and coal resources, so that various countries in the world are attaching importance of the recycle and purification of CO2. Many countries are studying on the cyclic utilization of carbon dioxide. Gas CO2 is mainly applied in chemical, pharmaceutical raw materials, beverage filling agent, refrigerant, inert medium, solvents, pressure source, the welding protective gas, antioxidant and fire extinguishing agent, etc. Solid CO2 is mainly applied in penicillin production, fish, cream, ice cream and other food storage and transportation at low temperature, etc. nowadays, such methods as absorption method, membrane separation, adsorption, etc. are widely used to recycle CO2, with such problems as high investment cost and technical constraints etc."

Jan 1, 2014

By Jason Ganley, Yingjia Liu, Adam Dekich, William Tilson, Jeffrey Fergus, Dileep Kumar CJ

"Manganese cobalt spinel oxide coatings have been shown to be effective for preventing chromium volatilization from interconnect alloys, and the associated cathode poisoning, in solid oxide fuel cells. During high temperature exposure a reaction layer consisting of chromium containing spine! forms due to reaction with the chromia scale formed on the alloy. The electrical conductivity of this reaction layer is much lower than that of the coating material and thus can increase the overall area specific resistance (ASR) of the system. The approaches to reducing the ASR are to reduce the thickness and/or increase the electrical conductivity of the reaction layer, which includes both the high-chromium spinel phase and the chromia scale. In this paper the effects of transition metal dopants on the amount and properties of reaction products formed during the reaction of spine! oxide coating materials with chromia are presented.IntroductionThe high cost and difficulties involved with the processing of chromia based ceramic interconnect materials for SOFCs are driving the search for metallic interconnects [1, 2]. The reduction in the operating temperature of SOFC has allowed for the use of high chromium alloy steels for this application [3]. However, the volatilization of chromium from the chromia scale, and the associated poisoning of the cathode, remains a problem which needs to be addressed [ 4]. Though the application of manganese cobalt oxide spine! coatings on the alloy surface substantially reduces chromium poisoning of the cathode [5], the low electrical conductivity of the reaction layer formed between the chromia scale and coating affects the performance of interconnect. Incorporating transition metal ions in the reaction layer could alter the electrical characteristics and improve the performance. Copper and nickel doped manganese oxide spinels are widely used as thermistors due to their high electrical conductivity and negative temperature co-efficient of resistance characteristics [ 6, 7]. Hence doping of copper and nickel in manganese-cobalt spine! oxide composition may improve the electrical characteristics of interaction layer as well and is attempted here."

Jan 1, 2012

By K. C. Mills, P. N. Quested, A. P. Day, R. F. Brooks

"Methods have been developed to measure the physical properties of molten materials relevant to the fluid flow in high temperature processes. Data for the densities, viscosities and surface tensions of Al-, Ni- and Fe-based alloys are compared with (i) values for the pure metals and (ii) estimated values obtained from models making use of chemical composition of the alloy. Experimental values for metallurgical slags are also given and compared with estimated values.1 IntroductionPhysical property data has proved very useful in improving process control and product quality. For instance, in the continuous casting of steel the viscosity (TJ) of the mould flux is important since it determines (i) the optimum casting conditions, nVc = 2.5±1 dPas (m min-1) where V c is the casting speed and (ii) the level of slag entrapment (which leads to inclusions) in the metal. Thus data for properties like viscosity are exceedingly useful in understanding the process and the problems encountered and the causes of defects and problems.Another interesting development which has helped to increase our knowledge of processes and improve process control and product quality is the development of mathematical models of the fluid and heat flow in the process. These models have been developed to the stage where one of the prime requirements is for good physical property data for the industrial materials involved. Recently, Oxley [1] has shown that the use of reliable, experimental, property values for the commercial alloy in a commercial software package produced a significant improvement in the prediction of casting defects. Thus reliable property data are required for liquid metals but also for (i) liquid slags since many processes involve the use of a slag to refine and protect the metal or to lubricate the mould and (ii) refractories, sand and investment moulds."

Jan 1, 1999

By Sne?ana Devi

Mineralogy is a significant scientific discipline, essential in establishing the nature and the character of raw materials, regardless of whether they are monomineral or polymineral. Mineralogical characterization is very important, because its results give valuable information on features and nature of examined materials. Information's on mineralogical nature of mineral raw materials influence directly the quality assessment of a raw material, and thus the possibility of its use. The possibility of use of mineralogy in different industrial branches confirms constant activity of this scientific discipline. By use of methods within mineralogical analysis (optical microscopy, x-ray diffraction and others) data on mineral raw materials can be obtained as support in mineral raw materials quality assessment. Short description of results of mineralogical analysis of some mineral materials (granodiorite, dolomites, clay, refractory materials, slags and casting powders) in this paper shows the importance of its support to quality assessment and determine the possibilities of their use.

Jan 1, 2009

By Huimin Lu, Zhijiang Gao

Reduction reaction can happen among Al, V2O5 and TiO2 powders. Al can deoxidize metal V and Ti from the metal oxides. The electric igniter can be used to trigger the reduction. The reaction between Al and V2O5 is very intense and release large amounts of heat, but the heat which is needed to initiate the reaction between Al and TiO2 is not enough. These two reactions have been initiated first and V-Al and Ti-Al alloys can be obtained with a higher metal recovery percent. Through adjusting the ratio of Al, V2O5 and TiO2 powders, the system which combines these two reactions can ensured enough heat to react. KClO3 is added to the system, as the ignition agent, in order to make the reaction much complete. Finally, Ti-Al-V alloys can be obtained and need remelt to adjust the constituents.

Jan 1, 2016

By Chu Yong Cheng

Manganese is one of the main impurities in the recovery of base metals from their ores. This is especially true when laterite ores are processed using the pressure acid leach (PAL) process. The use of intermediate precipitation, solids/liquid separation and re-leach in the three Western Australian nickel laterite plants to separate nickel and cobalt from manganese and other impurities makes these processes complicated and costly in capital and operation. The research work carried out by the solvent extraction (SX) group at the A J Parker Cooperative Research Centre for Hydrometallurgy (CSIRO Minerals) has led to the development of direct solvent extraction processes to separate nickel and cobalt from manganese and other impurities. The simplicity of the process flowsheets and the expected savings in capital and operating costs are the major advantages of the new direct solvent extraction processes over the existing processes. By using a new synergistic organic system, Versatic 10 / dccyl-4-pyridinccarboxylatc ester, with a pilot plant leach solution from BHP¬Billiton (after iron precipitation), the metal values (Ni and Co) together with zinc and copper were separated from manganese and other major impurities (Mg, Ca and Cl) in the first SX circuit. The co-extracted manganese, magnesium and calcium were easily scrubbed out. The extraction and stripping kinetics of the metals with the new synergistic organic system were very fast and the synergistic system was found to be chemically stable. pH-extraction isotherms of metals with D2EHPA showed that the extraction order as a function of pH50 was Zn2+ > Ca2+ > Mn2+ > Cu2+ > Co2+> Ni2+> Mg2+. Semi-continuous test work with a cobalt pilot plant leach solution from Peko Rehabilitation Project Pty Ltd and a synthetic solution to simulate a concentrated laterite leach solution from BHP-Billiton showed that manganese, together with calcium, copper and zinc can be separated from nickel, cobalt and magnesium. This led to the development of another direct solvent extraction process to separate manganese and other impurities from nickel and cobalt and to recover nickel and cobalt from leach solutions. A project was initiated by HiTec Energy Ltd to recover manganese from waste laterite leach solutions using SX technology and to further purify it to produce high purity electrolytic manganese dioxide (EMD) for the high quality alkaline battery industry. Batch tests were conducted to select a suitable organic system for the extraction of manganese in terms of selectivity and extraction and stripping kinetics. A total of eight organic systems were tested using waste laterite processing solutions. A Versatie 10 / synergist system showed very promising results. By using the synergistic system, high manganese recovery would be obtained, fewer SX stages would be required and a higher A:O ratio could be used in extraction, resulting in a smaller organic inventory and lower capital costs. The risk of gypsum formation is also minimised with the synergistic system. Keywords: Solvent Extraction, Manganese, Laterite, Synergist

Jan 1, 2004

By Shengfan Zhou, XUEWEN WANG, Changjun Jiang, Mingyu Wang

In the process of extracting vanadium from stone coal by sulfuric acid leaching - P204 solvent extraction, Fe(III) can accumulate in the organic phase which reduces the extraction of vanadium. In order to eliminate the effects of the accumulation of iron, oxalic acid was used as the stripping agent to strip the Fe(III). The effects of oxalic acid concentration, phase ratio O/A, stripping time and shake velocity on the stripping of Fe(III) were studied. The results showed that the Fe(III) stripping rate can reach beyond 96% at the room temperature with 70g/L oxalic acid using an O/A of 2 at 160 rpm shake velocity for 20min. After 2-stage stripping, the concentration of Fe(III) in organic phase was 0.008g/L.

Jan 1, 2016

By Javier Antoñanzas, Susana Caballero, Eduardo Fernández, Jorge Aragón, Juan Carlos Múgica, Lourdes Yurramendi

Air Pollution Control (APC) residues treatment by plasma was studied as a technology for vitrification. During the project a protocol to verify the plasma technology was developed and afterwards applied to a specific case study: the APC residues from Municipal Solid Waste Incinerators (MSWI). Different operational conditions were tested and the vitrified products obtained were analyzed using standardized leaching tests in order to evaluate their new properties concerning safety storage. Two leaching tests were used for the evaluation, the European EN 12457-4 compliance test for leaching of granular waste materials and the French XP X 31-211 test for the determination of the leachability of a solid waste material initially massive or generated by a solidification process. Finally, conclusions about the environmental performances of the technology were obtained.

Jan 1, 2008

By Gerald M. Rich

Magma Copper Company, a subsidiary of Newmont Mining Corporation, has initiated many changes in the continuous casting of 5/16 inch diameter copper rod since startup of the San Manuel rod plant in early 1972. With rod production at forty percent over design capacity, many production records have been established including a record cast of 761 tons of salable rod in a twenty-four hour period. The most challenging and rewarding introduction was the continued utilization of an alloyed copper casting wheel in lieu of the conventional steel wheel. With proper cooling and careful control of the mold release agents. as much as 58.000 tons of copper were cast on a single copper wheel. Other advantages are: 1) Fifteen percent increase in available casting time 2) Reject rod from steel inclusions was reduced by nearly one-hundred percent 3) Wheel cost was decreased by ninety-one percent 4) Natural gas consumption dropped approximately fifteen percent 5) Large increase in refractory component life 6) Reduction of manhours/ton. Many other modifications have contributed to excellent rod quality and high operating efficiency. A two-piece launder was replaced with a single castable launder which reduced oxygen pickup and provided better slag removal. Modifications to the bar preparation unit, pickling system, and coiler resulted in considerably higher milling efficiency.

Jan 1, 1976

By Michael K. Rhodes

A 120 tonne per day BacTech bacterial oxidation plant treating refractory gold concentrates for Gold Mines of Australia's Youanmi project in Western Australia commenced operation September 1994. This was the first commercial application of the BacTech process. A pilot plant trial on concentrates produced from Youanmi ore was carried out at BacTech's laboratory in Perth. Results and measurements from this trial were used by Signet Engineering Pty Ltd to design the commercial plant. This paper cover the results obtained from the piloting, their implementation in the plant design and the initial commissioning of the full scale plant.

Jan 1, 1995

By T. S. Bannos

Section 1417 of the Safe Drinking Water Act Amendments enacted by the O.S. Congress prohibits the use of lead containing solders for potable water systems in new construction or when making repairs. The legislature defines "lead-free" solder as containing less than 0.2% lead. In the development of a new solder it was recognized in addition to the lead free requirement, the alloy should perform as well as the popular 50/50 tin lead solder, both in application and properties. Another objective was to have only nontoxic elements. This led to the development of a 4.0% copper, 0.5% silver and 95.5% tin solder. Review of the merits of other alloy systems and the development of the physical properties along with test data are presented for the lead free tin. rich alloy.

Jan 1, 1990