Study On Temperature Characterization Of Shock Energy Release Of Amorphous Alloy

Compared to metal / polymer fragments,amorphous alloy fragments exhibit excellent mechanical properties and higher density.The shock energy release reaction of amorphous fragments is mainly composed of the redox reaction between metal components and oxygen.The high-temperature products result in the heating of gas around the reaction area,causing a rapid expansion of gases and leading to overpressure damage.Additionally,the high-temperature reaction products can stick to the target,releasing heat continuously and demonstrating the ability for erosion and arson.Presently,the primary method for measuring the impact energy release of amorphous fragments is Venting Chamber Calorimetry(VCC),which can measure the total energy released by the fragments based on the peak value of quasi-static overpressure.However,VCC cannot further characterize the ablation effect that the fragments have on the target.The quasi-static overpressure caused by impact of amorphous fragments is mainly due to the endothermic expansion of gas,and temperature is the primary parameter used to measure ablation.Therefore,the peak temperature is a more reliable characteristic to describe the ablation efficiency and total energy release of the impact reaction of amorphous fragments.Currently,research on the temperature field change of the impact energy release of amorphous fragments mainly focuses on the temperature distribution of the debris cloud in open space and the ignition effect of the target behind the target.There are relatively few reports on the characteristics of the temperature field caused by the impact of the fragments in a confined space.In this paper,the mechanical properties of zirconium-titanium-based amorphous fragments and zirconium-niobium-based amorphous fragments were tested by universal compressor and SHPB device.The changes of temperature field in the container after the amorphous fragments hit the quasi-static chamber were measured by thermocouple,and the effects of element composition and impact velocity on the energy release characteristics were studied.Based on Ls-dyna ’s FEM-SPH algorithm,the impact of zirconium-copper-based spherical amorphous fragments on the chopping block after penetrating the 2A12 aluminum end cover of 2mm was studied by numerical simulation.The experimental results show that titanium can provide greater plastic deformation ability for amorphous fragments,and niobium can improve the elastic modulus of amorphous fragments.The two types of thermocouples have the same effect on the ablation of the target,and the temperature measurement curve of shock energy release is repeatable and reliable.Under the same conditions,the ablation effect of zirconium-titanium-based fragments on the target is better than that of zirconium-niobium-based fragments,and the critical velocity threshold corresponding to the maximum energy release efficiency of zirconium-titanium-based fragments is lower than that of zirconium-niobium-based fragments;the highest temperature of energy release at different speeds can be indirectly obtained by placing powders with different burning points in the chamber,but the powder affects the measured results of temperature.The simulation results show that the hot spots inside the fragments are distributed on the interface between the crack and the impact,the number of hot spots is related to the impact velocity and loading strain rate,the small step impact peak has a certain activation effect on the amorphous fragments,and the amorphous fragments hit the chopping board.start releasing energy quickly.