I-Corps: In-situ Non-Destructive Evaluation for Higher Yields at Metal Additive Manufacturing Installations

Louisiana State University, Baton Rouge LA

Investigators

Abstract

The broader impact/commercial potential of this i-Corps project is safer and more reliable 3D printed metal structures, also commercially known as additive manufactured parts. The project will explore the needs of the 3D printing industry as the technology is applied to ever more demanding areas such as aerospace and automotive. In aerospace, each component must be produced by a verified and validated procedure, and in-situ inspection can meet that need. In the automotive industry, representative components must be evaluated to verify production procedures and equipment operation; again, in-situ inspection can meet this need. In addition to aerospace and automotive, 3D printed metal structures are expected to have wide commercial applications, ranging from health to defense. In these applications, safety and reliability are paramount. For example, a 3D printed replacement for a broken bone must be highly resistant to breakage itself. However, the mass limitations for a bone replacement require efficiency in design and a trust in fabrication. This I-Corps project is a non-destructive evaluation (NDE) method that is used to observe the metal structure while it is being printed or upon completion of the manufacturing process. Historically, metal parts must be subjected to destructive inspection methods to meet high reliability requirements after manufacturing. This alternative NDE is based on a novel X-ray imaging method, grating-based interferometry, first introduced about ten years ago. In this method, micro-fabricated X-ray optics are used to enhance the X-ray image, especially for the detection of sub-micron features. The traditional X-ray image is improved with an overlay image that reveals the presence of sub-micron features. Recently, sub-micron features in 3D printed metal components have been correlated with preliminary crack formation under fatigue stress. Therefore, an X-ray grating-based interferometry image of a freshly printed structure (either in-progress or completed) can reveal the presence of failure points. By demonstrating the viability of this unique NDE methodology to potential users of 3D printed parts, it is anticipated that new market segments can gain sufficient confidence in part reliability to incorporate these 3D printed parts into critical components. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.