Research on energy absorption of gradient porosity structural materials

Abstract

Different from traditional subtractive manufacturing, additive manufacturing is a layer by layer process which is easier to manufacture complex shape. Among the commonly used metal additive manufactured materials, Ti-6Al-4 V (Ti64) exhibits the characteristics such as low density, good mechanical properties, and lightweight. According to the characteristics mentioned above, Ti64 is a good candidate for structural materials. In this study, porous structures/bionic structures were introduced to evaluate the capacity of energy absorption, namely orthogonal, as shown in. Meanwhile, the porous Ti64 materials were designed with gradient porosity from 50 % to 90 %. All the samples were manufactured using selective laser melting (SLM) technology and tested by compression testing. Through compression testing, the energy absorption capacity of these gradient porosity materials with different porous structures and changes in porosity can be evaluated according to the yield stress, strain at failure, and Young's modulus, meanwhile, toughness and specific energy absorption can also be calculated. The porous structures and changes in porosity induced energy absorption variations are discussed in detail in this study.