Studio e ottimizzazione del processo di fabbricazione additiva (SLM) per applicazioni in ambito biomedicale: produzione di protesi e strutture reticolari

This dissertation presents the development of an experimental method for the production of personalised prostheses by additive manufacturing; specifically, Selective Laser Melting (SLM). The aim of this thesis is to optimise the process for surgical applications, ensuring the reproducibility of prosthesis characteristics independently of variations in patient anatomy. The work follows two main lines of study, whose convergence has allowed the production of prostheses using a single process. Firstly, the production of maximum density components with high mechanical strength and good wear and corrosion resistance was carried out. Subsequently, lattice structures with controlled porosity were studied to promote the osseointegration of implants. Relationships between the process parameters and final properties of SLM components were identified. Based on these results, a new manufacturing strategy was developed for prosthesis production. The performed experiments and obtained results demonstrated feasibility of the SLM process for production of personalised prostheses. Following this outcome, the first functional prototypes were produced. The manufacturing of patient-specific prostheses also requires the design and production of personalised surgical instruments. Experimental tests on AISI 316L components were therefore carried out. It was also possible in this case to identify a process window that guarantees comparable mechanical properties with conventional processes.