22 research outputs found
Effect of build geometry on the β-grain structure and texture in additive manufacture of Ti 6Al 4V by selective electron beam melting
Automated Multi-Scale Microstructure Heterogeneity Analysis of Selective Electron Beam Melted TiAl6V4 Components:english
Selective Electron Beam Manufacturing of Ti-6Al-4V Strips: Effect of Build Orientation, Columnar Grain Orientation, and Hot Isostatic Pressing on Tensile Properties
Evolution of microstructure and intervariant boundaries of α phase in electron beam melted and heat-treated Ti–6Al–4V alloy
Influence of build layout and orientation on microstructural characteristics of electron beam melted Alloy 718
Effects of build layout and orientation consisting of (a) height from the build plate (Z-axis), (b) distance between samples, and (c) location in the build plate (X-Y plane) on porosity, NbC fraction, and hardness in electron beam melted (EBM) Alloy 718 were studied. The as-built samples predominantly showed columnar structure with strong Ë\u82001Ë\u83 crystallographic orientation parallel to the build direction, as well as NbC and ÎŽ-phase in inter-dendrites and grain boundaries. These microstructural characteristics were correlated with the thermal history, specifically cooling rate, resulted from the build layout and orientation parameters. The hardness and NbC fraction of the samples increased around 6% and 116%, respectively, as the height increased from 2 to 45 mm. Moreover, by increasing the height, formation of ÎŽ-phase was also enhanced associated with lower cooling rate in the samples built with a greater distance from the build plate. However, the porosity fraction was unaffected. Increasing the sample gap from 2 to 10 mm did not change the NbC fraction and hardness; however, the porosity fraction increased by 94%. The sample location in the build chamber influenced the porosity fraction, particularly in interior and exterior areas of the build plate. The hardness and NbC fraction were not dependent on the sample location in the build chamber. © 2018, The Author(s).First Online: 17 September 2018</p