Quality Control of a Metallic ALM Part

Overview

Additive Manufacturing (AM) is a valuable tool for the space industry, particularly when combined with non-destructive methods such as X-ray computed tomography to inspect and analyze defects. When combined with Finite Element Modeling (FEM), the effect of defects in parts can be quantified.

In this project, an aluminium AM part used for the TARANIS satellite was analyzed to identify the location of porosities within the material. Simpleware was used to generate the model for FEM to validate its structural integration, using a random vibration model and comparison with results from CAD modeling and topological optimization.

Characteristics:

X-ray CT data of aluminium part segmented and processed in Simpleware ScanIP
Simpleware FE Module used to generate a mesh for simulation in ANSYS Workbench
Results validated AM method for comparing CAD models and designed part, with space mission applications

Thanks to:

ELEMCA: J. Uzanu, J. Dhennin
Synopsys: M. Nixon, D. Harman
CNES: J.M. Desmarres

References:

Anon. (2017) Quality control for additive manufacturing parts using non-destructive testing. Aerospace & Defense Technology.

Image Processing

Image segmentation in Simpleware ScanIP

X-ray CT scanning (V Tome X System, GE, Phoenix) was used to acquire image data of the aluminium part, including defects. Simpleware ScanIP was used to segment the main body of the component from the image space, creating an initial mask of the structure; all regions of the mask disconnected from the main body were discarded. Painting and threshold-assisted painting employed to accurately segment the structure and reduce the influence of metal artefacts.

Meshing

Mesh generated in Simpleware for export to ANSYS Workbench

Smoothing was applied to the segmented geometry to increase surface smoothness prior to meshing. The geometry was meshed using the Simpleware FE Module algorithm to automatically generate a coarse mesh while maintaining the detail of features of interest. A mesh refinement region was applied to the top part of the structure and node sets added to screw hole regions. The final mesh was exported to ANSYS Workbench 17.1 for simulation.

Simulation Results

Von Mises stress simulation in ANSYS Workbench

The final mesh was used in ANSYS Workbench 17.1, with boundary conditions set up using node sets in Simpleware. Simulations using the image-based models were developed for comparison to previous CAD simulations, including a comparison of Von Mises stress between the models.

Conclusions

The study validated the AM process by inspecting X-Ray CT scans of the part, and used a high-quality mesh for simulation of performance. Comparison of experimental, CAD and FEM results was effective at considering deviations between designed models and scanned geometries. This workflow is useful for adding new levels of quality control and analysis to AM processes within the space industry. The part has been successfully tested, and may now be integrated into the space mission.

Acknowledgements

This study is integrated within a larger project known as ALMIA (Additive Layer Manufacturing for Industrial Application). SOGECLAIR Aerospace leads this project with CNES, FUSIA, RATIER-FIGEAC and ICA. The goal of the project is to define and validate a new AM process for space application, from concept to realization. This case study focuses on a single part, made from the aluminium alloy AS7606, that is planned for integration on a TARANIS satellite.