Titlebook: Metallurgy of Welding; J. F. Lancaster Book 1980 J. F. Lancaster 1980 metallurgy.metals.welding

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Introductory,oldering and the hammer welding of gold appear to have been known during the Bronze Age, but they were mainly used for making ornaments. Welding first evolved as a technique of primary economic importance when the use of iron became widespread, it being required not only in order to make finished pr

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Mass and heat flow in welding,tal and heat-affected zone. Mass flow, which encompasses the flow of plasma in the arc column, the flow of metal from electrode to weld pool, and the flow of metal in the weld pool itself, has less influence on the metallurgy of the joint. Irregularities or instabilities in mass flow may, however, l

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Austenitic and high-alloy steels,25% Cr. Hardenable high-alloy steels are arbitrarily classified as those containing more than 20% of alloying elements but which are capable of being hardened by heat treatment. The corrosion and oxidation resistance of these steels results from the formation of a self-healing surface film of chromi

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Non-ferrous metals, aluminium-zinc solders have also been used to a limited extent. Fusion welding was first accomplished by the oxy-acetylene process but is now carried out by means of GTA and GMA welding and sometimes using coated electrodes. The power source for GTA welding is usually an a.c. transformer with high