Lightweight 3D printed Ti6Al4V-AlSi10Mg hybrid composite for impact resistance and armor piercing shielding

Abstract

In this research, metallic lightweight ductile composites made from Ti and Al alloys are tested against dynamic impact. 3D printed Ti6Al4V cellular lattice structures with different strut diameters and cell sizes were sintered inside an AlSi10Mg powder during the low-pressure low-temperature process and investigated experimentally and analytically. Four novelties of the present study are: (1) Ti6Al4V-AlSi10Mg composite with local or overall impact reinforcement, (2) combination of selective laser melting (SLM) and spark plasma sintering (SPS) techniques to produce hybrid composites, (3) multiple impact test method with in-situ monitoring of sample acceleration, (4) coupling of SolidWorks and ANSYS finite element software to model and simulate penetration depth, stress distribution, deformation of uniform and gradient architecture lattices due to projectile impact. The volume fraction of the Ti6Al4V lattice (influenced by cell size and strut diameter) has a pivotal role in impact resistance. The results show that composites with smaller cell size with thinner strut diameter has similar performance to those with larger cell size with thicker struts, due to equal volume fraction. The good performance of the thickest strut possible per unit cell demonstrates the pivotal role and direct relationship of the volume fraction of the Ti6Al4V lattice for the impact resistance. In addition, the simulation results show that a uniform lattice structure with a higher volume fraction leads to a shallow penetration, while a gradient lattice hinders shape distortion.