Using X-ray Diffraction to Determine Stresses
In recent years 3D printing has emerged as an increasingly intriguing technology: used to create toys, models, and even full size houses. Though most common in plastics, 3D printing is being considered for commercial metal products as well. As in other casting and processing techniques, the properties of materials that are 3D printed can vary greatly. For example, in the manufacturing of hot metals, controlled cooling is necessary to avoid embrittlement. In 3D printed metals, one property of particular concern is residual stress, as it can cause metal parts to warp when cut free from their base plates. It is therefore, important to understand how the 3D printing process effects the distribution of the stresses in parts. High energy x-ray diffraction (HEXD) is one of the tools that can be used to investigate residual stresses. HEXD measures volumetric strain profiles, which can then be analyzed to find out more about the stress characteristics of the part. We will use these profiles to measure the residual stress depth in several aluminum bars and present the results.