Vibration Behaviour of Topologically Optimised Sacrificial Geometries for Precision Machining of Thin-Walled Components
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View abstract on PubMed
Summary
This summary is machine-generated.Optimized geometries for additive manufacturing (AM) improve modal performance but increase vibration sensitivity during machining of thin-walled titanium components. These findings are crucial for advanced aerospace applications.
Area Of Science
- Materials Science and Engineering
- Mechanical Engineering
- Manufacturing Processes
Background
- Additive manufacturing (AM) offers component consolidation and integrated functionalities in metallic parts.
- Layered fabrication in AM often leads to surface roughness and geometric inaccuracies.
- Machining is essential for improving surface finish and dimensional accuracy of AM components, especially thin-walled structures.
Purpose Of The Study
- To investigate the vibrational behavior of thin-walled Ti6Al4V components produced via laser powder bed fusion (L-PBF).
- To evaluate the impact of different stock envelope designs (constant, tapered, and two optimized variants) on modal characteristics during machining.
- To assess the influence of optimized geometries on modal performance and machining-induced vibrations.
Main Methods
- Fabrication of thin-walled Ti6Al4V jet-engine compressor blade demonstrators using L-PBF.
- Evaluation of four stock envelope designs: constant, tapered, and two topologically optimized variants.
- Modal analysis using tap testing before and after machining to assess changes in vibrational characteristics.
Main Results
- Optimized geometries enhance modal performance without increasing material volume.
- Topologically optimized designs show greater in situ modal changes during machining compared to constant or tapered designs.
- Increased variability in material removal and chip load in optimized designs amplifies vibration sensitivity.
Conclusions
- Optimized stock envelope designs can improve the inherent modal performance of additively manufactured components.
- Machining of optimized AM parts, particularly thin-walled structures, requires careful consideration of increased vibration sensitivity.
- Further research is needed to mitigate vibration challenges in machining complex AM geometries for enhanced performance in demanding applications.
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