Abstract
Electric discharge machine developed in late 1940’s has been accepted worldwide as a standard process in manufacturing and is capable of machining geometrically complex or hard material components, that are precise and difficult-to-machine such as heat treated tool steels, composites, super alloys, ceramics, nitrated alloy, carbides, heat resistant steels etc. EDM has become an important and cost-effective method of machining extremely tough and brittle electrically conductive materials. It is widely used in the process of making moulds and dies and sections of complex geometry and intricate shapes. The work piece material selected in this experiment is EN-41 alloy steel taking into account its wide usage in industrial applications. In today’s world EN-41 alloy steel contributes to almost half of the world’s production and consumption for industrial purposes. The input variable parameters are current, pulse on time and duty cycle. Taguchi method is applied to create an orthogonal array of input variables using the design of experiment (DOE). The effect of the variable parameters mentioned above upon machining characteristics such as material removal rate (MRR), tool wear rate (TWR) is
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It is thus a thermal erosion process. The sparks are created in a dielectric liquid, generally water or oil, between the work piece and an electrode, which can be considered as the cutting tool. There is no mechanical contact between the electrodes during the whole process. Since erosion produced by electrical discharges, both electrode and work piece have to be electrically conductive. Thus, the machining process consists in successively removing small volumes of work piece material, molten or vaporized during a discharge. The volume removed by a single spark is small, in the range of 10-6-10-4 mm3 but this basic process is repeated typically 10,000 times per
Entropy is not a difficult concept to just take at face value, but it is a difficult topic to gain a good understanding of. To do this some background must be given such as the first and second law of thermodynamics. The second law of thermodynamics states that any event that occurs spontaneously must result in an increase in the randomness of lhe syslem. This means that as an ice cube melts the water molecules that it is composed of will progress toward a less ordered arrangement. The leaves that fall from the trees do nol arrange themselves in a pile on the ground because the second law of thermodynamics is against it. Entropy is a concept that most high school chemistry and physics students enjoy learning about because the now have an excuse for having a messy room, they are fighting nature.
It works by three main ingredients. Electricity, filler metal, and a form of shielding from the air are very important (gowelding para 2). “Just like MIG welding, Flux Core welding works by feeding an electrode continously to the joint” (gowelding para 2).The first step is the welder squeezes the trigger and a spool of wire is fed to the joint into the arc. As soon as the electrode hits the metal it heats it up until the wire and weld area begin to fuse together. Once the puddle is made the Flux Core creates a shield from the air (gowelding para 2). The power supply is a constant voltage power supply. This means the welding machine uses a direct current just like MIG welding, as the same machine is used for both types of
Light! What is it? Where does it come from? What can we do with it to help humanity? It allows us to see the unknown the places that have been dark for years. It helps us see what is around us. Different sources of light can be used to power the things around us. Lightning is a source of light.
First, let me give you some background information on MIG welding. MIG welding was created in the 1940s and is a type of welding in which a wire is fed through a roller and into a gun. The gun has a trigger that controls the amount of electricity and speed of the wire coming out. Once the wire coming out of the gun touches metal it will create an arc of electricity. A non-reactive gas also comes out of the gun at the same time as the wire. The gas used is 100% Argon or a mixture of CO2 and argon. The gas shields the wire as its being welded. This arc heats up the wire coming out and once cooled down the metal is now conjoined together.
... cutting which uses a flame-fired torch using oxygen and propane in conjunction with iron powder is also used to cut steel. This method is clean and fast. Plasma jet cutting, is another method that uses an ionized gas column in conjunction with an electric arc through a small orifice. The gas produces extremely high temperatures to melt the metal. (Chater, 2010)
Many parts, for example, screws, nuts, bolts, and fittings, are produced by automatic turning operations [10]. Some alloying elements sometimes added to impart special characteristics to brass. Lead, which is insoluble in copper alloys, is used to improve machinability of leaded brass. However, Pb and Bi or other elements that are used to improve the machinability often deteriorate the low and high temperature ductility of brass [11]. The content of Pb element is varies between 2.5 and 3.5 %, which make the machining processes at high speed and good surface [12]. The solubility of lead in copper alloys is very low therefore, it is found in microstructure as dispersed globules all over the material. These globules lead act as a lubricant decreasing the friction coefficient between the tool and the material by creating discontinuities of chip fragmentation. Therefore, it makes reducing in cutting force and then, the tool wear rate is minimized [13]. Different alloying elements help to improving the machinability are usually added to brass. The most common element using in this situation is lead, which improving the machinability with regard to excellent chip breakage, low tool wear and high applicable cutting parameters. These aspects can be explained by two basic phenomena; first of all, the solubility of lead in brass is extremely low and lead segregates in the entire microstructure, particularly at the grain boundaries. Hence, shear strength is reduced, resulting in very good chip breakage. Secondly, lead exhibits a low melting temperature and during cutting process, a thin, semi-fluid lead film reduces friction with cutting forces
Micro Electro-Mechanical Systems (MEMS) is the integration of mechanical elements, sensors, actuators and electronics on a common silicon substrate using microfabrication techniques. MEMS are a hot area of research because they integrate sensing, analyzing and responding on the same silicon substrate hence promising realization of complete systems-on-a-chip. As MEMS are manufactured using batch fabrication techniques similar to IC technology, MEMS are expected to deliver high functionality at low prices.
Using manual welding, it is very tricky to achieve the utmost standards of quality and safety. This is mainly due to ce...
The Physics of an Electric Motor An electric motor is a device used to convert electric energy into rotational kinetic energy. There are two different types of electric motors, and each has its own use. The different types are direct current and alternating current motors. Each of these motors will be analyzed in the following steps.
There is a highly controlled cooling process that takes place over many days and allows the carbon atoms to build up on top of the diamond seed. The growth cell is removed from the HPHT machine once the growth cycle is complete. The new rough diamond is cleaned and now ready for final cutting and polishing.
In some Greek experiments, objects attracted each other after rubbing. Other experiments produced objects that pushed away, or repelled, each other. The evidence showed that electric force made matter either attract or repel other matter.
To have a general understanding of the steelmaking process, it is best to understand the most common method of producing steel, the blast furnace. The blast furnace is a chemical process used to create iron from raw materials. Among the vast number of early metallurgical processes used throughout history, the blast furnace is still one of the most economical methods to produce iron. Iron ore, coke, and limestone are charged into the top of the furnace where numerous chemical processes take place. Hot blasts of air enter the bottom of the furnace through nozzles called tuyeres. Dirty gas travels out of the furnace through uptakes and then through a downcomer. Particles settle out in a dustcatcher and a scrubber removes fine particles. Clean gas can now be burned. Once the raw materials have smelted into molten pig iron, a drill breaks through the tap-hole and iron flows out into a trough. Slag is removed with a skimmer and processed for applications in concrete. Molten iron is collected in a ladle and transported for further production. The mud-gun fills the tap-hole with refractory clay and more materials are charged into the ...
Electrical motors play an important role in today’s society, from powering domestic appliances like blenders to industrial equipment such as trains. It almost seems impossible to not use an electric motor in our daily lives. In the comfort of our home, electric motors will operate fans, refrigerators, and air conditioners to just name a few. Researchers are constantly looking for new ways to incorporate electrical motors in our lives.
...tarters are important and essential part where ever the electric motor is used, as discuss above in the without it motor starts at extremely high current, by this many unwanted things will occur, such as by increasing the current the distribution company should equipped there system (machines) rated as the starting current which is draw only for few seconds (till getting some specific RPMs) also industries get it expensive without starter to use electric motor in their application.
Machine tools are the machines which are used to provide special shape and form to the material by different machining operations. There are different kinds of machines tools that are available and can be used for different machining operation. In today’s era, productivity and accuracy are the two most important point of concern for any manufacturing industry. There are various natural and human made forms of error that reduces the machine accuracy which led to loss of productivity, efficiency, setup time and loss of money. [1]