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Micro texture on cutting tool inserts obtained via laser micro-machining has recently emerged as an environment friendly method to reduce adhesion on the tool’s rake face and to improve friction conditions during machining. However, these benefits are strictly correlated with a correct design and behavior of the texture to be replicated on the tool surface. This paper reports an experimental study of developing an array of dimples on both rake and flank of commercial, cemented carbide cutting inserts using a picosecond laser source. Experiments of orthogonal dry cutting on E235 steel tubes were performed using textured and untextured tools to evaluate the improvements obtained. The improvements achieved were assessed in terms of cutting force and their impact on cutting performances. A predictive finite element model was developed to optimize the design of the dimples, to be replicated onto the rake surface of the tool.

Drawing of wires is a well known process and several manuscripts are recognizable looking at the scientific literature. The main reason why the process is used is related to increasing of the elastic resistance of the materials thanks to the induced yielding. Nevertheless many information are available from a mechanical point of view, today new needs related to process sustainability push toward a process redesign taking into account different criteria. In this paper, a multi-objective approach based on the optimization of a set of objectives is presented. Process force, die wear, material thinning and damage are considered building an optimization problem in which the technologist can decide the role of each criterion in the operative scenario.

Although the competitiveness of Incremental Sheet Forming process can be recognized by the literature review, some intrinsic aspects penalize its industrial application. In particular, even if the idea to take advantage from the bigger formability appears of great interest, on the other hand the not homogeneous thickness distribution reduces the industrial suitability. However, a significant improvement in the thickness distribution can be obtained by using an “artificially modified” tool trajectory. In fact, previous experimental investigations carried out by the authors showed that it is possible to influence the thinning phenomenon by applying a proper tool trajectory. The present study was executed with the aim to design a robust procedure able to highlight how to modify the tool trajectory in order to improve the thickness distribution along the profile. More in particular, the study is based on the coupled use of the numerical analysis and the Taguchi's method. All the results are widely discussed in the paper.

Single-point incremental forming (SPIF) presents a great competitive advantage with respect to the conventional stamping processes, in particular when small batches have to be produced. The competitiveness of such a process cannot be evaluated only by comparison with other traditional manufacturing processes. It is clear that the process allows metal forming in the critical ‘necking-to-tearing’ zone and this results in a strong thinning before failure if the process is well designed. What is more, the process is complex because of the number of variables involved. Thus, it is not possible to consider that the process has been well assessed; several aspects remain that must be clarified. In this paper a wide-ranging investigation of tool trajectory selection versus material formability is presented. In particular, although the same shape has to be manufactured, it is possible to select a particular trajectory among the many possible ones; this choice will affect the final thickness distribution and formability, accordingly. In conclusion, it is possible to state that tool trajectory can be regarded as an optimization variable in the process design.

New trends in sheet metal forming are rapidly developing and several new forming processes have been proposed to accomplish the goals of flexibility and cost reduction. Among them single point incremental forming operations, in which the final shape of the component is obtained by the relative movement of a simple and small punch with respect to the blank, appear quite promising.

Incremental forming is an innovative sheet metal forming technology in which a blank is plastically deformed through the progressive action of a small-size punch, whose movement is governed by a CNC machine. In this way the tool locally deforms the material through an almost pure stretching deformation mechanics.