Copper and copper alloys are widely used in the aqueous environmental application because of their properties in such environment, copper and copper alloys are antimicrobial, they are also have strong mechanical and corrosion resistant properties in aqueous environmental. The combination of these properties has made them a desirable material for many kind of aqueous environmental applications such as condenser tubing, water intake screens, offshore structure, drinking water piping and cooling systems of electrical generators. One of the most widely used methods of joining copper and its alloys is brazing.
Many different types of pure metals and alloys of brazing filler materials are developed, they are available in a variety of forms, they are foil, paste, sheet, powder, wire, rod etc. This to reduce the difficulties of the process putting them between the base metals as various metals have different physical shapes and properties. The process requires a lot of attention and care in order to minimize the gaps in the metals that are being joined which could lead to failure of the brazed joints. The basic qualities of these filler metals that are prerequisites for the successful base metals bonding are : strength, workability in high temperatures and corrosion resistance. There is a large number of metals and alloys and all of them have different compositions, which makes it a critical point to carefully compare and choose the filler metals. The properties and characteristics of the filler metals should essentially match the properties of the base metals to be joined..
However, filler metals are generally divided based on their working temperatures. Aluminum and aluminum alloys commonly brazed with filler metals that the working ...
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...ium brazing alloy,” US Patent Publication, Pub. No. : US 2012/0288401 A1, United States of Americaa, 2012.
[6] D. R. Sigler, J. G. Schroth, Y. Wang, D. Radovic, Sulfide-Induced Corrosion of Copper-Silver-Phosphorus Brazed Joints in Welding Transformers, Welding journal, 340-348, vol.86, 2007.
[7] A. Valero-Gomez, A. Igual-Munoz, J. Garcia-Anton, “Corrosion and Galvanic Behavior of Copper and Copper-Brazed Joints in Heavy Brine LiBr Solutions,” Corrosion (2006).
[8] Joseph A. Worden, Jorge M. Mundulas, Understanding, Diagnosing, and Repairing Leaks in Water-Cooled Generator Stator Windings,GE Power Systems, Schenectady, NewYork, 2008.
[9] B.Kempf, E. Sjöstrom, D. Kaufmann, J. Breme, Universität des Saarlandes Saarbrücken, W. Weise, University of Applied Sciences Esslingen, New Filler Metals for Brazing of Stainless Steel. Deutsche Gesellschaft für Materialkunde.
We use metals to construct all kinds of structures, from bridges to skyscrapers to elevators. The strength as well as durability of materials that are crafted out of metal make the materials ideal not only for construction but also for many other applications.
Stainless steel, especially, Austenitic stainless steel, because of their high corrosion resistance and customizable mechanical properties has become an indispensable part of the regularly evolving modern day technology. Stainless steels of various grades find applications in numerous fields starting from the household to the nuclear reactors; from food and beverage cans to construction of different automobile parts. The formation of impervious oxide layer on the surface makes it suitable for use in adverse environments such as sea water.
Martensitic stainless steels have good mechanical strength and moderate corrosion resistant. Because of their excellent corrosion resistance and mechanical strength, martensitic stainless steels are used for manufacturing the steam turbine blades, heat exchangers, automotive components and structures, petrochemical & process piping. Properties of martensitic stainless steel can be changed by the heat treatment. Increasing productivity of any welding process while maintaining or even improving the weld quality has been the task of researchers in the field of development of welding processes. Over the years welding methods and techniques have developed to great extent [3]. Now it is feasible to weld starting from thin metal sheets of fraction of mm to very thick plates of virtually any thickness. The quality of welding is not restricted only to work done by the welder but depends on many other factors, viz. welding technique and its parameters, welding equipment shielding medium, working environment, etc.
"Production of Refractory Metal Powders," in Powder Metal Technologies and Applications, vol. 7, 1998, pp. 188-201.
Schlesinger, Mordechay. "Electrochemistry Encyclopedia." Electroplating. Department of Physics, University of Windsor, Sept. 2002. Web. 17 Nov. 2013.
John Walker, from the book Modern Metalworking states that before welding to check the welder to make sure the leads and the grounds are connected properly because the temperature of the weld is determined by amps (2). There are different sizes of rods, these include eighteen gauge, sixteen gauge, ten gauge, one-eighth gauge, three-sixteenth gauge, and one-fourth gauge (Walker 30-4). When welding be sure to have the correct welding speed. Weld speed is indicated by the looks of the puddle and the ridge of the bead (Walker 30-14). Rob Timing from FabricationandWelding.com states that the filler metal fills the cavity made when
INCONEL (nickel-chromium-iron) alloy 600 is a standard engineering material for applications which require resistance to corrosion and heat. The high nickel content gives the alloy resistance to corrosion by many organic and inorganic compounds and also makes it virtually immune to chloride-ion stress-corrosion cracking. Chromium confers resistance to sulfur compounds and also provides resistance to oxidizing conditions at high temperatures or in corrosive solutions. The composition of Inconel 600 is listed in Table
A wide variety of coating alloys and wrought alloys can be prepared that give the metal greater strength, castability, or resistance to corrosion or high temperatures. Some new alloys can be used as armor plate for tanks, personnel carriers, and other military vehicles.
The Electrolysis of Copper Sulphate Aim Analyse and evaluate the quantity of Copper (Cu) metal deposited during the electrolysis of Copper Sulphate solution (CuSo4) using Copper electrodes, when certain variables were changed. Results Voltage across Concentration of solution electrode 0.5M 1.0M 2.0M 2 5.0 10.6 19.5 4 10.5 19.8 40.3 6 14.3 26.0 60.2 8 15.2 40.4 80.3 10 15.0 40.2 99.6 12 15.1 40.0 117.0 Analysing/Conclusion The input variables in this experiment are; concentration of the solution and the voltage across the electrodes. The outcome is the amount of copper gained (measured in grams) at the electrodes. By analyzing the graph, we can see the rapid increase of weight gained for the 2.0 molar concentration as the gradient is steeper.
Remus, R., Roudier, S., Aguado-Monsonet, M. A. and Delgado Sancho, L. 2013. Best available techniques (BAT) reference document for iron and steel production. Luxembourg: Publications Office.
Aluminum is one of a number of soft metals that scientists call "poor" metals. It can be shaped and twisted into any form. It can be rolled into thick plates for armored tanks or into thin foil for chewing gum wrappers. It may be drawn into a wire or made into cans. Aluminum is a generally popular metal because it does not rust and it resists wear from weather and chemicals. (Bowman, 391) Aluminum is an element. Its atomic number is thirteen and its atomic weight is usually twenty-seven. Pure aluminum melts at 660.2ºC and boils at 2500ºC. Its density is 2.7 grams per cube centimeter. Aluminum is never found uncombined in nature. (Bowman, 391) Aluminum is a very useful metal that is light, easy to shape and can be strong. This makes aluminum one of the most used metals in the world, right behind iron and steel. (Geary, 185) In its pure state, aluminum is quite weak compared to the other metals. However, its strength can be greatly increased by adding small amounts of alloying elements, heat-treating, or cold working. Only a small percentage of aluminum is used in its pure form. It is made into such items as electrical conductors, jewelry, and decorative trim for alliances and cars. A combination of the three techniques has produced aluminum alloys that, pound for pound, are stronger than structural steel. Some common metals used in alloys for aluminum are copper, magnesium and zinc.(Walker, 31) The added elements give the aluminum strength and other properties. (Newmark, 41) Aluminum is one of the lightest metals. It weighs about 168.5 pounds per cubic foot, about a third as much as steel which weighs 487 pounds per cubic foot. (Neely, 214) As a result, aluminum has replaced steel for many uses. For example, some ...
The basis for the understanding of the heat treatment of steels is the Fe-C phase diagram. Because it is well explained in earlier volumes of Metals Handbook and in many elementary textbooks, the stable iron-graphite diagram and the metastable Fe-Fe3 C diagram. The stable condition usually takes a very long time to develop, especially in the low-temperature and low-carbon range, and therefore the metastable diagram is of more interest. The Fe-C diagram shows which phases are to be expected at equilibrium for different combinations of carbon concentration and temperature. We distinguish at the low-carbon and ferrite, which can at most dissolve 0.028 wt% C at 727 oC and austenite which can dissolve 2.11 wt% C at 1148 oC. At the carbon-rich side we find cementite. Of less interest, except for highly alloyed steels, is the d-ferrite existing at the highest temperatures. Between the single-phase fields are found regions with mixtures of two phases, such as ferrite + cementite, austenite + cementite, and ferrite + austenite. At the highest temperatures, the liquid phase field can be found and below this are the two phase fields liquid + austenite, liquid + cementite, and liquid + d-ferrite. In heat treating of steels the liquid phase is always avoided. Some important boundaries at single-phase fields have been given special names. These include: the carbon content at which the minimum austenite temperature is attained is called the eutectoid carbon content. The ferrite-cementite phase mixture of this composition formed during cooling has a characteristic appearance and is called pearlite and can be treated as a microstructural entity or microconstituent. It is an aggregate of alternating ferrite and cementite particles dispersed with a ferrite matrix after extended holding close to A1. The Fe-C diagram is of experimental origin. The knowledge of the thermodynamic principles and modern thermodynamic data now permits very accurate calculations of this diagram.
Socket Weld flanges were firstly developed for use on small-size high pressure piping. Their static strength is equal to Slip On flanges, but their fatigue strength 50% more than double-welded Slip On flanges. The connection with the pipe is done with only 1 fillet weld, at the outside of the flange. But before welding, a space must be created between flange or fitting and pipe. The purpose for the bottoming clearance in a socket weld is usually to minimise the residual stress at the root of the weld that could occur during solidification of the weld metal. The disadvantage of this flange is the gap, that must be made. By corrosive products, and mainly in stainless steel pipe systems, the crack between pipe and flange can have corrosion
Metals possess many unique fundamental properties that make them an ideal material for use in a diverse range of applications. Many common place things know today are made from metals; bridges, utensils, vehicles of all modes of transport, contain some form of metal or metallic compound. Properties such as high tensile strength, high fracture toughness, malleability and availability are just some of the many advantages associated with metals. Metals, accompanied by their many compounds and alloys, similar properties, high and low corrosion levels, and affects, whether negative or positive, are a grand force to be reckoned with.
The element Aluminium has a symbol of Al and has an atomic number of 13. It is a very light, soft and useful metal used for many things such as cans, foil and kitchen utensils. It is a ductile metal, a good conductor of heat and electricity, does not corrode and is a solid at room temperature. It was discovered in 1825 by Hans Christian Oersted in Denmark. Aluminium is one of the most used metals in the world as well as one of the most commonly found metals in the Earth’s crust.