Solid/Powder Clad Ti-6Al-4V Alloy with Low Young’s Modulus and High Toughness Fabricated by Electron Beam Melting

Abstract

A clad structure that consists of solid and powder parts was created from powdered Ti-6Al-4V utilizing electron beam melting (EBM) technique by a single process. The input energy density required to melt the raw powder material was controlled by changing the scan speed of the electron beam from 100 to 2000 mm/s. The finished products showed several types of structures: a dense solid, a periodic layered (clad) structure made up of a solid part and an unmelted powder part, and almost full powder. The products with the clad structure showed a combination of low Young's modulus and high toughness as characterized by the presence of a stress plateau in the stress-strain curve. Both of these qualities are necessary for feasibility as implant materials used in orthopedic fields. We conclude that the products developed in this study could be useful as bone implants in terms of the mechanical similarity to bones, despite needing only an single EBM process for fabrication.

3D Puzzle in Cube Pattern for Anisotropic/Isotropic Mechanical Control of Structure Fabricated by Metal Additive Manufacturing

“…In addition, necking formation between powder particles by heat treatment can contribute to large energy absorption [31]. The post-processing treatment for necking the particles also contributes to suppression of the cytotoxicity of the materials by preventing the flow of the metal powders away from the devices [32]. The further functionalization of the structure using the above treatment method will be reported in our future report.…”

Effect of Multiple Reverse Transformation Treatments on Grain Refinement and Mechanical Properties of Biomedical Co–Cr–Mo–N Alloys Fabricated by Electron Beam Melting

“…The adhesion of unmelted powder on the outer surface was confirmed because the molten pool formed using electron beam irradiation can trap adjacent powder particles. [20] The calculated Ra was 22.76 μm. The SEM image demonstrates the cross-section of the AsB material on the plane perpendicular to the fabrication direction.…”

New Powder/Solid Composite Exhibiting Low Young’S Modulus and Energy Absorption for Biomedical Applications Fabricated by Additive Manufacturing

“…Recently, we developed another type of bone mimetic materials possessing low Young's modulus and high toughness by a single process of EBM without heat treatments [2]. By controlling electron beam scan speed to optimize thermal energy input into the powder in the RBM process, the clad structure made up of melted solid and powder parts with a relatively regular stacking was formed as shown in Fig.…”

“…We expect that new products composed of the solid and functionalized necked powder reported in this study will be beneficially utilized for biomedical and industrial applications. We report on the synthesis of a material combining a controllably low Young's modulus and excellent toughness as found in the related research works [1,2].…”