Thermite welding

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Thermite welding is the process of igniting a mix of high energy materials, also called thermite, that produce a metallic slag that is poured between the working pieces of metal to form a joint. It was developed by Hans Goldschmidt around 1895.

Commonly utilizing the composition of 5 parts iron oxide red (rust) powder and 3 parts aluminium powder ignited at high temperatures. A violent reaction occurs that produces through reduction and oxidation a white hot iron slag and vaporous aluminium oxide. This form of welding is still widely used to weld railway rails. This form of welding is also in use today for example for quick fixes on ship hull punctures and the likes. It is not particularly quality weld due to the fact of low to nil carbon content in the filling metal and low heat penetration into the joining metals. This method is usually used in conjunction with oxyacetylene flame to create a good fusion with the working pieces of metal.