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Case Hardening Purpose and Method of Steel Components

Introduction Steel components are used in many applications that require a hard and strong surface to resist wear and abrasion combined with a tough core to withstand shock and fatigue. This condition can be obtained by an alteration in the composition of the surface layer of a steel component followed by the application of a suitable “heat treatment. The surface region in which the properties and composition have been altered is known as the case, and the production of a hard surface is known as case hardening. In this process, the steel is caused to absorb such elements as carbon,…

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Heat Treatment Process of Industrial Tools

Introduction General purpose tools like chisel, hammer, file, punch, lathe tools etc. are manufactured by forging. These tools are normalized immediately after forging to restore their original structure and to relieve stresses and strains set up while forging. Hardening is carried out to induce hardness at the working end and simultaneously tempering is carried out to make the body tough to absorb shock while working. Hence heat treatment has got unique importance in the field of production industry as it helps to induce desired qualities which enable the tools to serve their purposes. Heat treatment of different tools is described…

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Types of Heat Treatment

Introduction Heat treatment is defined as an operation or combination of operations, involving heating and cooling of a metal or alloy in the solid state to obtain desirable properties. Heat treatment consists of three phases. Heating of the metal Soaking of the heat into metal Cooling of the metal Heating Heating temperature of metal for the purpose of heat treatment depends upon its grade, grain size, type and shape of a metal or alloy. Generally, the metal is never heated much beyond its upper critical temperature. Plastic deformation takes place because of heating. This deformation depends upon the chemical composition…

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Iron Carbon Equilibrium Diagram Explained

Introduction Alloys of the Iron carbon system are of the most vital importance to the modern industry due to their extensive, versatile applications. The Iron carbon system provides the most prominent example of heat treatment and property alteration based on the transformation from one form to other on application of heat and eutectoid decomposition. Because of its outstanding importance, the heat treatment of the iron-carbon system has been studied in more details than most alloy system. Types of steels and cast iron depend upon the percentage of carbon present in the steel or cast iron. As per the carbon percentage,…

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Purpose of Heat Treatment

Introduction Heat treatment is an operation or combination of operations, involving heating and cooling of a metal or alloy in the solid state for the purpose of changing the properties of the metal. Heat treatment consists of three phases. Heating of the metal. Soaking of the heat into metal. Cooling of the metal.  Purpose of Heat Treatment The purpose of heat treatment is as follows: To improve machinability. To improve mechanical properties, e.g., tensile strength, ductility, hardness and shock resistance. To relieve the stress induced during hot or cold working. To change or refine grain size. To improve magnetic and…

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Titanium & Zirconium Alloy Materials and Its Usage

Introduction Titanium is a chemical element with the symbol Ti and atomic number 22. Sometimes called the “space age metal”, it has a low density and is a strong, lustrous, corrosion-resistant (including sea water and chlorine) with a silver color. Titanium can be alloyed with Iron, Aluminium, Vanadium, and Molybdenum to produce strong lightweight alloys for aerospace (jet engines, missiles, and spacecraft), military, industrial process (chemicals and petro-chemicals, desalination plants, paper industry), automotive, orthopedic implants, and other applications Property A metallic element, Titanium is recognized for its high strength-to-weight ratio It is a strong metal with low density that is…

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Nickel Alloy Materials and Its Usage

Introduction Nickel is obtained commercially from oxide ores, arsenical ores, and ores of Copper, Manganese and Iron, at least 85 percent of all nickel production is obtained from Sulphide ores. Pure nickel is tough silver-coloured metal, rather harder than Copper and have about the same strength, but possessing somewhat less ductility. It closely resembles Iron in several of its properties. It is malleable, weldable, and perceptibly magnetic. But unlike Iron, it is little affected by dilute acids. It is far less readily oxidisable, and deteriorates much less rapidly under atmospheric influences than Iron. For this reason, articles of Iron and…

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Zinc Alloy Materials and Its Usage

Introduction The chief ores of Zinc are zinc blende (zinc sulphide) and calamine (zinc carbonate). In the extraction of the metal, the ore is first roasted in a reverberatory furnace to convert the sulphide to oxide, and in the case of calamine, to drive off carbonic acid and water. The roasted ore is then reduced either in a furnace or by electrolysis process. Zinc is fairly heavy, bluish-white metal used principally because of its low cost, corrosion resistance and alloying properties. The melting point of Zinc is 4190C. The protection of Iron and Steel from corrosion is done more often…

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Copper-Tin Alloy Materials and Its Usage

Introduction Bronze is an alloy composed mainly of Copper and Tin. The useful range of composition is 5 to 25 percent Tin and 75 to 95 percent Copper. The alloy is comparatively hard, resist surface wear and can be cast into shape or rolled into wire, rods and sheets very easily. In corrosion resistant properties Bronzes are superior to Brasses. It is used in hydraulic fittings, pump linings, making utensils, bearings, bushes, sheets, rods, wires and many other stamped and drawn articles. Some of the more common types of Bronzes and the special purpose Bronzes are described below. Phosphor Bronze…

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Use of Copper, Lead & Tin Alloy Materials

Introduction Copper is one of the most widely used non-ferrous metals in industry. It is not found in pure state from under the earth. It occurs in some minerals such as copper glance (Cu2S), copper pyrites (CuFeS2)’ malachite (CuCO3.CuO2H2) and azurite (3CuCO3.CuO2). In India, copper ores are found at Ghatsila in Bihar and Khetri in Rajasthan. Properties and Uses It is a soft, malleable and ductile metal with a reddish-brown appearance. Its specific gravity is 8.9 and melting point is 1083°C. It is a good conductor of electricity. It is largely used in making electric cables and wires, for electric…