Research Seminar: Towards the defect-tolerant design of 3D-printed parts

This seminar will be of particular interest to professionals and researchers working in manufacturing, materials science, and quality control in the area of Additive Manufacturing.

Professor Vladimir Brailovski, a leading expert in Mechanical Engineering from École de Technologie Supérieure (ÉTS), Montreal, Canada, will share insights from his cutting-edge research and practical experience.

Abstract

No one is perfect. Neither are 3D-printed parts generally containing a certain number of process-induced flaws, such as pores and inclusions. However, there must be a way to use them in challenging applications safely. The answer to this endeavour is to apply the defect-tolerant design principles. This approach, primarily developed for the aerospace industry, is especially pertinent for novel technologies, such as 3D printing, where there is a clear lack of relevant historical data. To establish the basics for defect-tolerant design of 3D-printed parts, two main objectives are generally established: a) assess the maximum size of process-induced flaws for which the printed part is still safe, and b) assess the minimum flaw size that can be detected in this part using a validated non-destructive testing (NDT) technique. To reach the first objective, a relation between the resistance of printed parts and the size of process-induced flaws must be established. To reach the second objective, a probability of detection (POD) of process-induced flaws using the selected NDT technique must be assessed.

These basic principles are illustrated using a Ti-6Al-4V alloy powder as a feedstock, laser powder fusion (LPBF) additive manufacturing technology to shape this material, and microcomputed X-ray tomography (CT) NDT technique to control the quality of printed parts. All these data are used to build a Kitagawa-Takahashi type diagram revealing the mechanical resistance of printed material as a function of the size of process-induced flaws and are equally instrumental for all the categories of personnel involved in the development of 3D-printed parts: designers, manufacturers and QC specialists.