Analyzing the effects of powder and post-processing on porosity and properties of electron beam melted Ti-6Al-4V

Abstract

Metal additive manufacturing techniques such as the powder-bed systems are developing as a novel method for producing complex components. This study uses synchrotron-based X-ray microtomography to investigate porosity in electron beam melted Ti-6Al-4V in the as-built and post-processed state for two different powders. The presence of gas porosity in the starting powder was shown to correlate to porosity in the as-built components. This porosity was observed to shrink after a hot isostatic press treatment, but grow following a subsequent heat treatment. Crystal plasticity simulations were used to observe the effects of various observed pore sizes on mechanical behavior under loading.

Keywords

• Additive manufacturing
• electron beam melting
• defects
• X-ray tomography
• crystal plasticity