Maria Grazia Violante

3D printing technique applied to rapid casting

Purpose – The purpose of this paper is to verify the feasibility and evaluate the dimensional accuracy of two rapid casting (RC) solutions based on 3D printing technology: investment casting starting from 3D‐printed starch patterns and the ZCast process for the production of cavities for light‐alloys castings.Design/methodology/approach – Starting from the identification and design of a benchmark, technological prototypes were produced with the two RC processes. Measurements on a coordinate measuring machine allowed calculating the dimensional tolerances of the proposed technological chains. The predictive performances of computer aided engineering (CAE) software were verified when applied to the ZCast process modelling.Findings – The research proved that both the investigated RC solutions are effective in obtaining cast technological prototypes in short times and with low costs, with dimensional tolerances that are completely consistent with metal casting processes.Practical implications – The research a...

Design and production of fixtures for free‐form components using selective laser sintering

Purpose – To introduce an innovative method for the design of supporting elements to be applied to the free‐form components during the dimensional control.Design/methodology/approach – This paper shows an innovative procedure based on reverse engineering and rapid prototyping techniques for the realization of fixtures fitting the geometry of free‐form elements. The application of the procedure have been made on a sheet metal free‐form element. After the design and manufacturing of the supporting elements, some uniformly distributed measurements have been made on the sheet metal component. A coordinate measuring machine (CMM) has been used in order to get dimensional information and to give the IT class location of the component.Findings – The use of the CMMs for the dimensional control of the production elements requires the availability of an adequate supporting system above all if the control concerns free‐form components with complex forms. This influences considerably the final quality of the measurem...

Study of the EDM process effects on aluminium alloys

Till now aluminium moulds have been employed only for pre-production; with the alloys A12219 and A17050, which have outstanding properties, we can think about medium productions of plastic components obtained by injection moulding. To evaluate the machinability of these alloys and understand the correlations among process parameters, dimensional tolerances, surface finish and electrode wear, some tests have been made by Electro Discharge Machining. The electrodes and the machined surfaces have been also observed at OM, SEM to understand the EDM mechanisms. Comparison tests have also been done on A17075, commonly employment for pre-production moulds, to have precise control data.