Quantitative analysis of surface texture in 3D printed metallic materials

• Main Author: Zhou, Shiqi
• Other Authors: Matteo Seita
• Format: Theses and Dissertations
• Language: English
• Published: 2018
• Subjects: DRNTU::Engineering::Mechanical engineering
• Online Access: http://hdl.handle.net/10356/74247
• Institution: Nanyang Technological University

Most metallic additive manufacturing (AM) technologies utilize a layer-by-layer approach to build three-dimensional (3D) parts. The layer-wise nature of AM provides the unique capability of inspecting the surface structure of each layer as they are built and thus to access volumetric information from bulk parts nondestructively. By assessing the layer surface structure, information about the physical phenomena involved during additive manufacturing as well as about the material’s quality can be inferred to better predict the performance of the final components or to correct the print “on the fly”. Novel optical microscopy techniques to quantify the surface morphology of 3D printed components are developed in this work. These techniques rely on the collection of a series of optical micrographs of the metal surface under controlled illumination conditions. The micrographs are processed using numerical image analysis methods and the surface morphology is reconstructed using a simplified Phong reflection model. Techniques developed in this report are amenable to rapid, non-contact, in-line analysis of surface features with a size larger than 0.1mm during AM.