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Abstract: 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. [Copyright &y& Elsevier]

Abstract: 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. [Copyright &y& Elsevier]

Abstract: Single Point Incremental Forming processes show some limitations related to both dimensional accuracy and process slowness. The process slowness is here overcome by introducing the high speed forming, which allows a reduction to less than 1min of execution time of target components made in Titanium alloys. The paper is aimed at analyzing the influence of the feed increasing on the material quality in order to investigate if the development of high speed machines could be a suitable solution to implement more extensively the Single Point Incremental Forming technique in practice. All the results are discussed in the paper. [Copyright &y& Elsevier]

Abstract: Porthole die extrusion is commonly used to manufacture hollow profiles made of lightweight alloys for numerous industrial applications. It is mainly based on the property of some alloys to weld at a solid state under proper conditions. In this study, an experimental campaign was designed to investigate the role of the process parameters affecting the process load and welding quality. The specimens were manufactured and tested measuring their strength. Finally, a 3D numerical simulation was performed in order to investigate the capability to predict the joint quality using a welding criterion. [Copyright &y& Elsevier]

In this paper an experimental investigation was conducted to determine the effects of the tool cutting-edge geometry, workpiece hardness, cutting speed, and microstructural changes (white and dark layers) on the residual stresses in dry orthogonal hard machining of AISI 52100 steel. X-ray diffraction technique was used to obtain in-depth residual stresses profiles in both axial and circumferential directions. The results show that tool geometry, workpiece hardness and cutting parameters significantly affect the surface residual stress, maximum compressive residual stress below the machined surface and its location. Moreover, microstructural analysis shows that thermally-induced phase transformations have a significant impact on the magnitude and location of this maximum compressive residual stress peak. [ABSTRACT FROM AUTHOR]

Abstract: In this paper an experimental investigation was conducted to determine the effects of the tool cutting-edge geometry, workpiece hardness, cutting speed, and microstructural changes (white and dark layers) on the residual stresses in dry orthogonal hard machining of AISI 52100 steel. X-ray diffraction technique was used to obtain in-depth residual stresses profiles in both axial and circumferential directions. The results show that tool geometry, workpiece hardness and cutting parameters significantly affect the surface residual stress, maximum compressive residual stress below the machined surface and its location. Moreover, microstructural analysis shows that thermally-induced phase transformations have a significant impact on the magnitude and location of this maximum compressive residual stress peak. [Copyright &y& Elsevier]

Abstract: In machining of hard parts, surface integrity is one of the most specified customer requirements. Often, the major indications of surface integrity are surface roughness and residual stresses. However, the material microstructure also changes in machined-hardened steels, and it must be taken into account for improving product performance. In this paper, a hardness-based flow stress and an empirical model for describing the white and dark layers formation were developed and implemented in a FE code. The proposed model was validated by comparing the predicted results with the experimental evidences. [Copyright &y& Elsevier]

Abstract: Industrial application of magnesium alloy AZ31 is dramatically increasing due to the very competitive mechanical strength vs. weight ratio. On the other hand, AZ31 is very difficult to be formed at room temperature. In this study incremental forming of the above material is taken into account, with particular reference to formability limits. The role of the main process parameters on material formability was investigated through a wide experimental campaign and a rigorous statistical analysis. [Copyright &y& Elsevier]

Abstract: This paper presents a new procedure to evaluate the global heat transfer coefficient in orthogonal cutting. The knowledge of the actual heat transfer conditions is a fundamental issue as far as the life, tool wear and tool substitution interval are regarded. More in detail, an Arbitrary Lagrangian-Eulerian approach was utilised to model orthogonal cutting process and the numerical simulations were validated by making experimental tests for identifying cutting forces and internal tool temperatures. A mild steel was cut utilising both an uncoated (WC) and a coated (TiN) tool. On the basis of both experimental and simulative data, a consistent model of the global heat transfer coefficient as function of the local pressure and temperature at the tool-workpiece interface was developed. [Copyright &y& Elsevier]

Abstract: Among the innovative sheet metal forming processes, Single Point Incremental Forming (SPIF) represents the simplest and the cheapest one. Despite its relevant advantages, up to now no specific CAE tools for SPIF were developed and the tool trajectory is generally defined utilizing CAD/CAM software developed for machining applications. In the paper an innovative monitoring and control approach, aimed to define and in-process update the most relevant process parameters during an industrial SPIF operation, is proposed. The strategy utilizes as monitoring variable the punch force trend: a set of preliminary tests demonstrated, in fact, its suitability as “spy variable” of the process mechanics and, in particular, of excessive sheet thinning and material failure approaching. [Copyright &y& Elsevier]