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In this paper, the analysis of surface changes and biocompatibility of Zr-702 additively manufactured bars have been performed. Samples were machined under dry and cryogenic environment at varying cutting speed and feed rate. Afterwards, MC3T3-E1 osteoblast cells were seeded on the as printed and machined surfaces verifying how cells adhesion and proliferation change based on the involved process parameters after 24 h and three days of culture. As a result, a connection between surface characteristics and process cells adhesion and proliferation has been provided and used to assess the potential of machining process to modulate biocompatibility of the investigated material. [ABSTRACT FROM AUTHOR]

Nowadays, numerical modeling is becoming a valuable and powerful tool for designing and optimizing the production process, as well as improving the machined components quality. Particularly, the Finite Element Method permits to increase the knowledge on the machinability of difficult-to-cut metals, such as the titanium alloys. The aim of this work is to develop a 3D FE model as a tool for predicting cutting forces, temperature, and machining-induced microstructural alterations during semi-finishing turning Ti6Al4 V under dry and cryogenic conditions. The numerical model is experimentally calibrated and validated. [ABSTRACT FROM AUTHOR]

In the last few years, important step forwards have been made on Finite Element Simulation of machining operations. Wrought Ti6Al4 V alloy has been deeply investigated both numerically and experimentally due to its wide application in the industry. Recently, Additive Manufacturing technologies as the Electron Beam Melting and the Direct Melting Laser Sintering are more and more employed in the production of biomedical and aeronautical components made of Ti6Al4 V alloy. Fine acicular microstructures are generated by the application of additive manufacturing technologies, affecting the mechanical properties and the machinability. By the consequence, this peculiarity has to be considered in modelling the material behaviour. In this work, a numerical analysis of cylindrical external turning on Electron Beam Melted (EBM) Ti6Al4 V alloy is presented. A Johnson-Cook constitutive equation was implemented as a flow stress model and adapted with respect to the wrought Ti6Al4 V alloy. The model was calibrated and validated through the cutting forces and temperatures measurements acquired under dry and cryogenic lubricating conditions. [ABSTRACT FROM AUTHOR]

The main objective of this study is to implement a reliable FE model of the orthogonal machining of a Nickel based superalloy for the prediction of microstructural changes occurring during the process. A FE numerical model was properly calibrated using an iterative procedure based on the comparison between simulated and experimental results. A user subroutine was implemented in the FE code to simulate the dynamic recrystallization and consequently the grain refinement and hardness variation when orthogonal cutting of Nickel based superalloy is performed. Thus, Zener-Hollomon and Hall-Petch equations were implemented to predict the grain size and micro hardness, respectively. In addition, the depth of the affected layer was predicted using the critical strain equation. The obtained results proved the adequacy of the proposed model showing a good agreement between the simulated and the experimental results. [ABSTRACT FROM AUTHOR]