Force and thickness prediction with FEA of the cranial implants manufactured through SPIF

Single point incremental forming is a process which is primarily used for prototyping, small series production and unique parts. This procedure shows a high potential in the development of complex shape parts where the time of the execution does not play an important role. Among the applications of this process are the execution of various medical prostheses, such as: knee prostheses and cranial implants. The aim of this paper is to determine the forces which take place during the manufacture process of an cranial implant, as well as the thinning of the material through the help of finite element analysis. After the numerical simulation, from the results obtained it is possible to observe the behaviour of the material at different forces which appear during the deformation process. In addition, in this paper will be presented considerations about the thinning of the material used for the cranial implant

Analysis of forming forces at SPIF using Taguchi method

Incremental sheet metal forming process has seen one of the highest increases in diversity in the last years. Single point incremental forming (SPIF) has become more attractive due to multiple benefits it possesses over other conventional cold forming processes such as deep-drawing. However, the process has yet to arise in the large-scale industrial implementation because of its drawbacks such as high production time and low accuracy, which lead to prototype production. A very important aspect for this manufacturing process is the analysis of the form-ing forces in terms of process energy especially when using industrial robots. The aim of this paper is to investigate the influence of material and vertical step over the forming forces. Thus, aluminum and steel sheets with a thickness of 0,8mm were incrementally deformed as a truncated cone with an angle of 60°, at a depth of 30mm. Experiments were performed using a KUKA KR 210-2 robot which allows to measure the forces using a piezoresistive sensor. After performing the analysis of the forming forces using the Taguchi method, it can be observed that the material has the highest influence

Experimental Research on the Behaviour of Metal Active Gas Tailor Welded Blanks during Single Point Incremental Forming Process

The present paper aims to study the behaviour of Metal Active Gas (MAG) tailor welded blanks during the single point incremental forming process (SPIF) from an experimental point of view. The single point incremental forming process was chosen for manufacturing truncated cone and truncated pyramid shaped parts. The same material (S355) and the same thickness (0.9 mm) were selected for the joining of blank sheets because the main goal of the paper was to study the influence of the MAG welding process throughout the SPIF process. A Kuka robot, equipped with a force transducer and an optical measurement system were used for manufacturing and evaluating the parts by SPIF. The selected output data were major and minor strain, thickness reduction, forces and springback at the SPIF process. Another line test was performed to evaluate the formability in SPIF. The main conclusion of the paper is that during the SPIF process, fractures occur in one side welded blanks even at moderate wall angles, while in the case of double side welded blanks there is a decrease of formability but parts can still be produced at moderate angles (55 degrees) without any problems