Invention Reference Number
Directed energy deposition (DED) is an additive manufacturing technique that enables rapid fabrication of metal components with high degrees of design flexibility. However, it is limited by challenges such as residual stresses induced by non-uniform heating, which can cause deformations, defects, and process failure. Prior strain or thermal monitoring methods require unacceptable process modifications and fail to deliver effective coverage for complex components, which necessitates the development of an advanced multimodal solution.
Description
This technology introduces a method and system for in-situ stereo digital image correlation (DIC) and thermal imaging during DED processes. The system tracks surface features in 3D over time, leveraging the natural roughness of the additive build, and constructs a strain history for the component as it is being built. Infrared imaging is also spatially registered to this 3D representation to measure the full thermo-mechanical behavior of the component. This innovative approach eliminates the need for applied speckle patterns, enabling real-time monitoring and control feedback in a nondisruptive way. The detailed strain and thermal data facilitates the detection and correction of defects such as delamination or cracking, direct validation of physics models, and rapid process optimization.
Benefits
- Real-time monitoring: Continuous, in-situ data capture and analysis during the DED process.
- Flexible: Demonstrated in all classes of DED (wire or powder; laser or arc welding).
- Low-cost solution: Highly affordable relative to machine costs or other inspection methods (XCT)
- High precision: Accurate 3D mapping comparable to blue light scanning, with sub-pixel strain resolution and full temperature range infrared imaging.
- Robust: Optical and algorithmic filtering of process noise for maximum process coverage.
- Defect detection: Early identification and correction of deformations and defects.
Applications and Industries
- Aerospace: Data enabled process quality metrics for critical components.
- Automotive: Accelerates process optimization for achieving rapid design iteration.
- Energy: De-risks production lead times for complex or large-scale components for energy systems, including turbines and reactors.
Contact
To learn more about this technology, email partnerships@ornl.gov or call 865-574-1051.
