Determinazione dello stress residuo mediante diffrazione dei raggi X delle leghe AlSi10Mg ottenute attraverso la produzione additiva

Additive Manufacturing (AM) is a new technology developed in the last 10 years. Most of the work has been conducted using polymeric materials, but the development of new routes, such as Direct Metal Laser Sintering (DMLS), Electron Beam Melting (EBM) and Laser Engineered Net Shaping (LENS), enabled to build functional parts using different materials, like metals, ceramics and composites. Additive Manufacturing uses data obtained through computer-aided-design (CAD) software or 3D object scanners to direct hardware to deposit material, layer upon layer, in precise geometric shapes. Although the terms "3D printing" and "rapid prototyping" are casually used to discuss this topic, each process is actually a subset of AM. It is possible to use different substances for layering material, including metal powder, thermoplastics, ceramics, composites, glass and even edibles like chocolate. Nowadays, the main industrial interest is in automotive, aerospace and aircraft applications, but another interesting field of research is the one related to biomedical applications. Among the metallic materials used for Additive Manufacturing applications we can find Aluminium alloys, Cobalt-Chromium alloys, Steels, Titanium alloys, Inconel and Gold alloys. In this work we will focus our attention on the study of residual stresses in AlSi10Mg samples, provided by Polytechnic of Torino where the DMLS-AM technology has been implemented, by means of X-Ray Diffraction (XRD). The samples are obtained through AM using the same feedstock material but different process parameters. By considering results obtained from XRD analysis on all samples, we have tried to establish which is the best approach to study stresses and if different process parameters affect the formation of stresses checking at the same time the reproducibility of the measurements, homogeneity of the stress in the samples and stress evolution during penetration analysis.