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Composites with 60~90% of tungsten are used in liners of some specialty shaped charges. The penetration is enhanced by a factor against copper for homogeneous steel target. Tungsten powder based shaped charge liners are also especially suitable for oil well completion. In this study, WCu composites manufactured by different process are used for testing of dynamic tensile extrusion (DTE) behaviour. One samples were made by copper infiltrated method. The other samples were manufactured by metal injection molding methods with reduced tungsten copper composite powder. DTE tests were carried out by launching the sphere samples (Dia. 7.62mm) to the conical extrusion die at a speed of ~375m/s. The DTE fragmentation behaviour of tungsten copper composites after soft-recovered were examined and compared with each other.

Ti-6Al-4V has become the most common material in titanium alloy. Due to High specific strength, low density and excellent mechanical properties, it has been used in not only living, sports goods but also aerospace, defense industries. Usually these products have complex geometry, so there are a lot of limitations in general manufacturing process. Especially in weapon systems, applied loadings are severe therefore choice of materials is very important. 3D printing method is useful for manufacturing these complicated structure and suitable to discontinued, superannuated part of products. In this study, specimen for experiments is turned out by using 3d laser deposition technology which metal powder is injected into the focused beam of a high-powered laser. While lots of studies are mainly concerned with normal process, it is not commonly researched for metallic materials forming through 3D printing. In the 10-3~103/s strain rates range, two kinds of plate samples and LDAM Ti-6Al-4V were performed using universal testing machine and SHPB for dynamic material properties. Simplified Johnson-Cook constitutive equation parameters produced from these experiments.

The dynamic deformation behaviours of SCM 440 steel were characterized at the strain rates from 10-3 s-1 to 106 s-1. The uniaxial tensile tests at different temperature of 25 °C, 350 °C, and 700 °C were performed by a hydraulic universal testing machine equipped with a heating stage, and the compressive tests were conducted by using a spilt Hopkinson pressure bar (SHPB) at room temperature. Material coefficients of the Johnson-Cook constitutive model considering temperature effects were obtained based on the stressstrain relations from the experimental tests. In addition, Taylor impact tests on the SCM 440 steel were carried out to evaluate the accuracy of the determined material coefficients and characterize the dynamic behavior at the ultra-high strain rates and high temperature, by comparison with numerical simulations.

The equal channel angular processing (ECAP) is a severe plastic deformation technique which can produce ultrafine-grained (UFG) alloy. This paper investigate the static and dynamic behaviour of ECAPed OFHC-Cu to evaluate possibility of its application to defence industries. Tensile tests were carried out at two different strain rate (10-3/s, 1/s) using digital image correlation (DIC) technique. High strain rate experiments were conducted using the split Hopkinson pressure bar (SHPB). The results were compared with forged OFHC-Cu and additional heat treated OFHC-Cu after processed by ECAP. Flow stress and strain sensitivity of ECAPed OFHC-Copper were increased compare to forged OFHC-Copper. After ECAPed copper heat treatment, the yield strength decreased with increasing of the average grain size. And numerical simulation of ECAPed copper shaped charge was performed using Autodyn hydrodynamic code.