Mesoscale simulation on the shock response of functionally graded Al-PTFE material

In this paper, the shock response of functionally graded Al-PTFE granular composites is firstly investigated by means of mesoscale simulations. A tailored arrangement of granular filler is infiltrated with matrix to study the effects of density gradient on mechanical and chemical characteristics of the material under impact loading. Based on the shock wave propagations, noticeable differences among pressure, temperature, and strain response are visualized at the grain-level. Results demonstrate that higher pressure is concentrated in the shock wave front and decrease over time. Moreover, a much greater energy-releasing and higher strain deformation exhibit along the grain/matrix interfaces. Compared with uniform reactive material, the functionally graded reactive material with decreased density gradient has a higher initial velocity in wave propagation, and the sample with increased density gradient has superior capability in wave attenuation, and a higher level of hot-spots concentration.