Mejoramiento de las propiedades mecánicas del estuche de latón 70/30 empleado en cartuchería militar

Abstract

The 70/30 brass alloy (C26000) is predominantly used for the production of cartridges helmets because it has excellent properties to resist severe stretched and sausages during production. However, several investigations have been published on the analysis of failures and malfunctions of the helmets manufactured brass when they are subjected to extreme pressures. These studies have mainly associated the failure of hull with the failure of the mechanical properties like tensile strength, yield point and hardness, to absorb the high pressures that the hull is under, so what has been determined to increase the mechanical properties of material to remedy the failure. The brass alloy of cartridge does not respond to usual treatments like hardening tempered or tempering, for it was a cold-hardening from a given grain size and using different percentages of cold work (36, 28, 38 and 60%). Then we proceeded to apply at each stage of the process of recrystallization heat treatment controlling grain size and subsequently apply as much strain to bring the material to nearly the limit of rupture. This thesis topic is to improve the mechanical properties of the hull of the cartridge, in order that the brass can withstand higher pressures than conventional. To this goal the material was characterized before and after treatments by techniques such as x-ray diffraction, optical microscopy, Vickers hardness and tension studies to analyze the microstructure, morphology and mechanical properties. An increment of tensile strength and yield in 25.02 and 23.45% was obtained, respectively. Also experimental batch was produced with the procedure described in the body of the thesis and these new helmets and had no swelling when subjected to high pressure or malfunction.19% was obtained like final result.