Effect of Process Parameters and Build Orientation on Microstructure and Impact Energy of Electron Beam Powder Bed Fused Ti-6Al-4V
Abstract
:1. Introduction
2. Materials and Methods
2.1. Materials
2.2. Experimental Methods
3. Results and Discussion
3.1. Mechanical Properties
3.2. Microstructure
3.3. Fractography
4. Conclusions
- A series of five EBPBF Ti-6Al-4V process parameter sets were investigated in terms of their resulting microstructure and impact energy across the vertical and horizontal build orientations.
- Vertically oriented specimens revealed an average increase in impact energy of 34% compared to the horizontally oriented specimens when beam velocity was less than 500 mm∙s−1, attributed to the epitaxial grain structure and its alignment to the Charpy test crack plane.
- Beam velocity was the parameter shown to have the most significant influence on impact energy, which reduced by 69% and 36% for the vertical and horizontal oriented specimens, respectively, when beam velocity was increased from 310.0 to 778.6 mm∙s−1.
- Microstructural characteristics of α lath width, prior β grain width, and prior β grain area were determined and related to process parameters and impact energy.
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Parameter Set | q | v | h | l | E0* |
---|---|---|---|---|---|
(W) | (mm∙s−1) | (mm) | (mm) | (J∙mm−2) | |
1 | 300 | 778.6 | 0.15 | 0.07 | 3.80 |
2 | 300 | 491.3 | 0.095 | 0.07 | 9.55 |
3 | 300 | 491.3 | 0.15 | 0.07 | 6.03 |
4 | 300 | 491.3 | 0.24 | 0.07 | 3.80 |
5 | 300 | 310.0 | 0.15 | 0.07 | 9.55 |
Build Orientation | Parameter Set | Energy Absorbed | SD | Impact Energy | SD |
---|---|---|---|---|---|
(J) | (J∙cm−2) | ||||
Vertical EBPBF | 1 | 29.1 | 1.9 | 36.4 | 2.4 |
2 * | 47.0 | 0.3 | 58.7 | 0.4 | |
3 | 46.0 | 1.1 | 57.5 | 1.4 | |
4 | 49.1 | 3.8 | 61.3 | 4.7 | |
5 | 59.5 | 2.9 | 74.4 | 3.6 | |
Horizontal EBPBF | 1 | 22.2 | 1.2 | 37.0 | 2.1 |
2 | 26.7 | 1.7 | 44.5 | 2.9 | |
3 | 24.9 | 1.7 | 41.4 | 2.8 | |
4 | 23.6 | 0.7 | 39.3 | 1.1 | |
5 | 31.8 | 1.9 | 53.1 | 3.2 | |
Cast ** | 34.1 | 3.8 | 42.7 | 4.8 |
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Jeffs, S.; Lancaster, R.; Davies, G.; Hole, W.; Roberts, B.; Stapleton, D.; Thomas, M.; Todd, I.; Baxter, G. Effect of Process Parameters and Build Orientation on Microstructure and Impact Energy of Electron Beam Powder Bed Fused Ti-6Al-4V. Materials 2021, 14, 5376. https://doi.org/10.3390/ma14185376
Jeffs S, Lancaster R, Davies G, Hole W, Roberts B, Stapleton D, Thomas M, Todd I, Baxter G. Effect of Process Parameters and Build Orientation on Microstructure and Impact Energy of Electron Beam Powder Bed Fused Ti-6Al-4V. Materials. 2021; 14(18):5376. https://doi.org/10.3390/ma14185376
Chicago/Turabian StyleJeffs, Spencer, Robert Lancaster, Gareth Davies, William Hole, Brenna Roberts, David Stapleton, Meurig Thomas, Iain Todd, and Gavin Baxter. 2021. "Effect of Process Parameters and Build Orientation on Microstructure and Impact Energy of Electron Beam Powder Bed Fused Ti-6Al-4V" Materials 14, no. 18: 5376. https://doi.org/10.3390/ma14185376