RESEARCH GROUP COMPUTED TOMOGRAPHY

UNIVERSITY OF APPLIED SCIENCES UPPER AUSTRIA - RESEARCH & DEVELOPMENT LTD.

ADAM - Advanced Multimodal Data Analysis and Visualization of Composites based on Grating Interferometer Micro-CT Data

ADAM project duration: 01.03.2016 - 28.02.2019

Within recent years, the need for new, cost-effective, function-oriented, highly integrated, and light-weight components has strongly grown in many high-tech industries such as aerospace, automotive, marine, and construction. The drivers behind this trend are mainly found in the rising application demands regarding efficiency, safety, environment, and comfort. Among desired functional and -mechanical properties, the requirements on new materials and components include high strength, elasticity, durability, energy efficiency, and light weight. Unlike conventional materials such as aluminum, steel, or alloys, fiber-reinforced polymers (FRPs) – composites made of a polymer matrix reinforced with carbon, glass, or other type of fibers – fulfill these requirements to a high extent. To design new materials and components, detailed investigations and characterizations of FRP materials are vital. In industrial settings, FRP components and materials are nondestructively tested, e.g., by visual inspection, tapping, or ultrasonic inspection. However, conventional methods are increasingly facing their limits regarding accuracy, level-of-detail, and inspection time. To overcome these limitations, industrial 3D X-ray computed tomography (XCT) has received much attention in quality control due to its high spatial resolution and ability to precisely capture external and internal structures in one scan. Compared to other non-destructive testing methods for FRPs, XCT is yet the only method capable of delivering full 3D information for detailed inspection and quality control.

Motivation

Recent advances in 3D X-ray computed tomography hardware have enabled applying the principles of Talbot–Lau grating interferometry (TLGI) in the first commercially available laboratory XCT scanning devices for industrial applications. Grating interferometry methods possess a great potential in non-destructive testing of materials as they provide three complementary modalities in one scan (see Figure 1): absorption contrast (AC) resulting from attenuation of X-rays through a specimen, differential phase contrast (DPC) containing information about refraction of X-rays, dark-field contrast (DFC) providing information about X-ray scattering. The complementary nature of AC, DPC and DFC imaging modalities opens new possibilities for the characterization of material features that cannot be resolved by conventional absorption-based XCT.

adam

Figure 1: Projection images of a fiber-reinforced polymer sample acquired using a novel laboratory grating interferometry XCT system (University of Applied Sciences Upper Austria – Wels Campus SkyScan 1294 system).

Goals

In detail the following project goals are targeted:

Development of advanced tomographic reconstruction methods for TLGI data, generating high quality reconstructions even from a limited number of projection angles and for directly estimating the material parameters of interest.
Development of data fusion techniques, combinational and comparative visualization techniques enabling data overviews and detailed inspections, as well as visual analysis techniques for AC, DPC, and DFC-data of fiber-reinforced composites including bi- and multidirectional TLGI XCT data.
Evaluation of the research results and demonstration of the developed methods in a software prototype.
Dissemination of the research results and the acquired knowledge to foster the adoption of TLGI XCT inspection in industry; providing commercialization possibilities to the industrial partners and beyond.