SpaceNDT

Starting point / motivation

Advanced manufacturing and materials are a crucial part of European efforts for strategic non-dependence (ESA Cross-Cutting Initiatives). Both additively manufactured (AM) parts and polymer matrix composites (PMC) (Technical domain 24: Materials & Processes) have high priorities in the ESA technology harmonisation.

Space flight hardware premises high demands on performance and reliability of applied lightweight structures. Material limitations of flight structures are defined by the mission goals and stability and strength have to be guaranteed over the component´s lifetime.

Contents and goals

The main challenges in the manufacturing of failure safe aerospace materials and structures involve a detailed structural characterization, component design and optimization, thermo-mechanical behaviour, and structural health management. To achieve these goals, simulation based engineering as well as non-destructive (NDT) and thermo-mechanical testing are essential.

Methods

In the course of SpaceNDT (FHW, AAC, FOTEC, PEAK) we will establish a multi-modal and multi-scale NDT approach combining X-ray computed tomography (XCT), phase-contrast X-ray imaging (PCI), and infrared thermography (IRT). Digital shearography (DS), acoustic emission (AE), and ultrasound testing (US) complement those imaging technologies for specified components.

Using this combination, we quantify defect propagation, e.g. of cracks or delamination, in advanced materials including AM, PMC, and multi-material parts.

The first goal is to establish a comprehensive defect catalogue and NDT based protocols for the probability of defect detection. This is particularly valuable for AM components, since ECSS standards for the detailed characterization of metallic 3d printed parts are still not fully established. The second goal is to apply finite element analysis (FEA) to predict the influence of detected defects on fatigue life in selected AM, PMC, and multi-material components.

In SpaceNDT, we will quantify material properties during static and cyclic thermo-mechanical testing using XCT, PCI, IRT, and DS. Loading experiments will be carried out both in- and ex-situ. Using advanced NDT techniques we will gather detailed information about defect initiation and propagation that by far excel existing standard methods, e.g. in relation to sub-pixel micro-cracks and delamination. We will use this information to improve damage models by means of FEA simulations.

Expected results

Using this feedback approach, results from fatigue analyses can directly be used to optimize design criteria of components, also for the combination of AM with advanced composites in integrated structures. Eventually, our objective is to formulate general recommendations to optimize production parameters based on reference and real parts that are investigated in this project.

The ultimate goal of this project is the establishment of NDT protocols for the verification of damage tolerance in fracture-critical components in order to develop "Best Practise Analysis Guidelines" for AM, PMC, and multi-material parts.

The cross-cutting, multi-disciplinary approach of SpaceNDT complements European space activities while simultaneously strengthening Austria´s role as a powerful competitor and competent partner in the space sector in relation to advanced manufacturing and NDT.

Coordinator

FH OÖ Forschungs & Entwicklungs GmbH

Project partner

• Aerospace & Advanced Composites GmbH
• FOTEC Forschungs- und Technologietransfer GmbH
• Peak Technology GmbH

FH OÖ Forschungs & Entwicklungs GmbH
FH-Prof. PD DI Dr. Johann Kastner
Stelzhamerstraße 23
A-4600 Wels