Research Of Penetration Properties And Penetration Mechanismof W-Cu Alloy Shaped Charge Liner

The high density, high acoustic velocity and good ductility of W-Cu alloy make it one of the most potential materials for shaped charge liners(SCLs). Recently, compared with Cu SCL, the penetration depth of W-Cu SCL with the same structure is raised by about 30%. In order to investigate the penetration mechanism and the influencing factors of the penetration properties of W-Cu SCLs, through statically detonation tests and detailed microscopic analyses of recovered targets, the present work investigated the melting and compositional gradient of W-Cu jet, studied the effect of W particle size and the addition of alloy elements on the penetration properties and penetration mechanism of W-Cu SCL, and made a research of the effect of the interaction between targets and jets on the penetration properties of W-Cu SCL.Analyses of the characteristics and the penetration mechanism of W-Cu jet show that, during the jet formation process and the penetration process, W-Cu jet maintains good compositional homogeneity without any compositional gradient and the jet melts only during the penetration process. During the penetration process, W contains most of the energy in jet, performing as the main penetrator, and Cu performs mainly as the lubricant between jet and target. The serious interaction between jet and target resulted in the transverse dissipation of jet energy, resulting in the melting of jet and target. The melted W reacts with the melted Fe, aggravating the dissipation of jet energy. While the melted Cu acts as lubricant and reduce the interaction between W and targets, decreasing the consumption of jets energy.The addition of Zn and Ni successfully increases the dynamic mechanical properties of alloys, while the penetration properties of alloys are decreased. Actually, the addition of Zn and Ni seriously affect the lubrication effect of the binding phase in alloys, aggravating the transverse dissipation of jets energy. Moreover, the addition of Ni also improves the bonding strength between W particles and the binding phase, causing much more serious deformation of W particles, which consumes jets energy further.The detonation test results of the W-Cu SCLs on the three kinds of targets, titanium alloy, Cu and 45# steel, the effect of target materials show that, the penetration depth in Cu targets is the highest, and the depth in the titanium alloy is the lowest. During the penetration process, Cu doesn’t react with W, and the melted Cu lubricates jet and target, thus decreases the consumption of jets energy apparently. However, both Ti in the titanium alloy target and Fe in the 45# steel target react with W in the jet, consuming a lot of energy, besides, hard phases are formed during the reaction, which hinder the penetration of jets further.With the decrease of W particle size, the mechanical properties of W-Cu alloy increases, while the penetration properties of SCLs decrease. Small W particles tend to grow up and reunite during the sintering process, which decreases the homogeneity of W-Cu alloy, resulting in the unsymmetrically collapse of SCLs and the shunt of jets. The shunt of jets affects the effective weight of jets seriously. Moreover, the decrease of the W particle size could also increase the specific surface area of the particles, promoting the melting of W particles under high temperature and high pressure in a very limited time. Melted W react with targets much more easily, thus the decrease of the W finally aggravates the transvers dissipation of jets energy.