2.1 The Continuous Casting
The Continuous Casting is a highly efficient manufacturing process, whereby molten metal is solidified into long, semi-finished shapes with constant cross section for subsequent processing in the finishing mills. Every year around 1 billion tons of steel, 20 million tons of aluminium and over 1 million tons of nickel, copper and other metals are produced all over the world in this manner. Continuous casting is distinguished from other solidification processes by its “steady state” appearance. That is, the molten metal freezes against the mould walls and is withdrawn from the bottom of the mould at a rate which keeps the solid / liquid interface at a constant position with time, relative to an outside observer. The
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Therefore, flux powder constitutes one of the important factors for the stability of casting operation and is closely related to the surface quality of the extracted metal.
The lubrication also deeply affects the heat transfer and has a key role for the process robustness. The interfacial slag layer between the solidifying steel shell and the mould wall dominates resistance to heat removal and thus, controls mould heat transfer in the CC mould [3]. The rate of heat transfer across the shell-mould gap depends on the slag layer thickness and its thermal properties.
There are various parameters that govern the lubrication efficiency in a CC mould like slag properties such as melting, crystallization and temperature-dependent viscosity, mould oscillation, inlet steel jet velocity, casting speed etc. Accurate knowledge of the infiltration behaviour of powder into the gap between a mould and a cast metal and its change under different conditions is, therefore, indispensable for establishing the appropriate use of casting
The Shang Dynasty invented and, over the years, perfected the technique of casting a bronze vessel from a clay mold assembly, which this wine vessel has also been made from using those techniques (Cantor). This mold was formed around a model of the vessel and was then cut into sections that were carved or impressed in the desired design, in this case the braided or grid design, on the inner or outer surfaces. The decorated clay piece-mold was then fired and reassembled around a clay core. Small bronze spacers were used to hold the piece-mold and the clay core apart. Then, molten bronze was poured into the mold. Using this piece-mold casting technique helped the bronze worker to achieve greater sharpness and definition in any intricate design
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.
Die-forming of sheet metal has been around for thousands of years. Originally the metal was manipulated by hand and hammered into the depression, by utilizing crude grooves carved into wood or stone. This technique was used to make spouts, handles, and other forms. Since then, however; they have undergone a remarkable technological evolution. Mate-female conforming dies to create hollow forms by using hydraulic pressure or drop hammer pressure, changed die-forming forever (Paisin, 2013).
"Production of Refractory Metal Powders," in Powder Metal Technologies and Applications, vol. 7, 1998, pp. 188-201.
Bronzes are made by making two molds (one larger than the other), pouring melted bronze in...
-Developed and implemented strip casting overseas to eliminate a step in the steel making process
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
One main category of welding is arc welding. Arc welding uses a current sent from an electrode, through the base metal, and back into the ground clamp on your welder. This arc creates a tiny spot of immense heat that melts the metal around it, thus creating a weld puddle, or the puddle of molten metal. Within arc welding there are MIG, TIG, and stick welding.
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.
The manufacturing process of steel container or drum which is also known as liquid carrying container involves many processes. Although, there are different sizes of steel containers and different manufacturing process in most steel container manufacturing industries lately. There are also thousands of different steel alloy used in the production of steel containers. Furthermore, steel containers are made of sheet metal by soldering, brazing, spot welding, and seam welding. In addition to this, The Process of making steel containers involves rolling of metal sheet; welding the seam, making 90 degree bent on top and bottom of the container, making number of beads (according to size) and lastly reduce the diameter of one side of the container; fitting of lid to the containers, testing like pressure; coating internal (epoxy phenolic coating or plain) and external (stoving enamel gloss of various colour).
"Metal Melting 101 - How To." Motorcycle Cruiser. Shop Talk, 24 May 2009. Web. 28 Apr. 2014.
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.
Autoclave processing is widely used for producing high quality thermoset composites, these are used in various industries to process a wide variety of thermoset and thermoplastic materials [10]. Almost any shape of the composite parts can be cured in autoclaves as the gas pressure is applied isostatically, the only limitations is the size of the autoclave and require high capital to install autoclaves. Autoclaves are normally pressurized with inert gas like nitrogen or carbon dioxide and air, but air is prone to danger of a fire within the autoclave during the elevated cure temperatures. It is observed that the heated pressurized gas strikes the front door and flow back down the center of the vessel to heat the part, as the gas strikes the door it produces considerable turbulence in the gas flow which results in higher velocities and stabilizes as it flows towards the rear of the autoclave.
Annealing and tempering are not the same types of heat treatment. Annealing can be defined as heating the steel to aus...
molten gob to create a cavity in this process while it is in the blank mould and this results in a