Hi! It is George Xanthopoulos here! I have developed a metallurgical processing technique of simultaneously controlling the direction of grain, and enhancing the resultant tensile strength of a vacuum cast hollow round bar of type 316 stainless steel that will ultimately be used as a component cylindrical barrel of a reaction vessel of an adiabatic detonation calorimeter, witch is used to measure enthalpies of detonation of explosives. Firstly, all of the ingredients of the type 316 stainless steel are formulated in the right proportions in a foundry and cast in a vacuum in a hollow cylindrical mould to prevent the inclusion of gas bubbles or voids in the casting. Secondly, the casting is heated uniformly to a temperature below the critical temperature of the 316 stainless steel so that grain growth does not occur, and a hydraulic press is used to extrude the casting through an expanding tungsten carbide die on the interior cavity of the casting, and a constrictive tungsten carbide die on the exterior of the casting. This process will impart a highly compressed microcrystalline grain structure to the casting, and produce a uniaxial direction of grain.
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George Xanthopoulos
Enfield, South Australia
+61(4)52651966
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