Search results for "Tecnologie"
showing 10 items of 1379 documents
Energy Efficiency of Sheet Metal Working Processes: Where do we stand today?/Energieeffizienz in Prozessen der Blechumformung – eine aktuelle Standor…
2014
Due to increasing energy and resource costs at the one hand and upcoming regulations on energy and resource efficiency at the other, a growing interest of machine tool builders to the environmental performance of their machine tools can be observed today. The last decade, academic as well as industrial research groups started to assess the energy demand of discrete part manufacturing processes and indicated a significant potential for improvement [1]. In contrast to conventional machining processes (e.g. milling, turning…), (sheet) metal forming processes are still less well documented in terms of their energy demand [2]. In consequence, potential energy efficiency improvement measures for …
TIO2 brookite: Properties, synthesis and applications
2017
Brookite is one of the less studied polymorphic phases of titanium dioxide. Indeed, synthetic procedures affording brookite as a pure phase were not straightforward and have been only recently optimized. For this reason, brookite has received particular attention in the last years, especially as a promising photocatalytic material for environmental remediation and for the synthesis of valuable organic products. The present chapter will review the main synthetic methods reported in literature to produce brookite as a pure phase or mixed with rutile and/or anatase. Morphological, structural and electronic properties both of pure or variously modified brookite will be presented. The particular…
Subtractive versus mass conserving metal shaping technologies: an environmental impact comparison
2015
The scientific studies in the domain of environmental sustainability of metal processing technologies predominantly focus on conventional material removal processes, as milling and turning. Despite some exceptions, many other non-machining technologies, such as metal forming processes, are still not well documented in terms of their energy and resource efficiency. Moreover, to properly evaluate the environmental impact of a given process, a standing-alone approach is no longer sufficient. In order to offer a valuable contribution in the domain of metal shaping sustainability, the present paper proposes a thorough methodology entailing to compare, from the environmental point of view, two tr…
CNC Milling Machine Simulation in Engineering Education
2012
In this work an effective simulator for a CNC milling machine is presented. It has been developed in EMC2, a free Opens Source NC software running in Linux environment, developed by an international community. It can be installed on a common PC and is able to: control a CNC machine; read part programs; display the tool path; send instructions to the CNC machine for the cutting process. In this work a new feature has been implemented, which can both display a 3D model of the machine and simulate all the motions of the movable parts of a real 3 axis end milling machine. This simulator lets the users not only verify the toolpath but also detect any possible collision by using the very computer…
Joining by plastic deformation
2013
Abstract As the scale and complexity of products such as aircraft and cars increase, demand for new functional processes to join mechanical parts grows. The use of plastic deformation for joining parts potentially offers improved accuracy, reliability and environmental safety as well as creating opportunities to design new products through joining dissimilar materials. This paper aims to provide an overview of the state of the art in such joining processes, including cold welding, friction stir welding, self-pierce riveting, mechanical clinching and joining by forming. The paper includes description of the mechanism of joint formation, and analysis of joint performance and applicability.
Sustainability for 3DP Operations
2020
Sustainability is an essential consideration in manufacturing, and within this chapter a detailed appraisal is given to sustainability for 3D printing. An in-depth review of existing research is provided, and a cradle-to-grave assessment technique is shown to assess the environmental impact of 3D printed part.
ALE Simulation of Orthogonal Cutting: a New Approach to Model Heat Transfer Phenomena at the Tool-Chip Interface
2007
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 f…
A Critical Analysis on the Friction Modeling in Orthogonal Cutting of Steel
2007
Numerical simulation of cutting process is today moving towards two different directions. The former concerns the development of high performance codes able to approach the 3D phenomena, the latter is already focused on the study of some fundamental aspects whose full understanding may be strategic for the knowledge enhancing in this very complex field. In the paper this second way was pursued and a wide analysis on the numerical robustness of the 2D orthogonal cutting process is presented. In particular, the role played by the friction modeling is discussed taking into account a wide integrated numerical and experimental campaign.
A Laboratory Scale Equipment to Relieve Force and Pressure in Cold Extrusion of Lead Hollow Components
2008
Nowadays, many researchers are involved in studies aimed to the explanation of some peculiar aspects regarding manufacturing processes. In this paper, an experimental campaign was carried out in order to reproduce tube extrusion starting from a cylindrical billet. In particular, the development of a proper equipment is presented: the aim was to measure both the total load, by using the testing machine load cell, and the local pressure value on the porthole. The latter task was carried out performing a proper system based on the use of a small load-cell. The tube was extruded with a good surface quality and the external area does not show any welding line evidence. Pure Lead was used for the…
3D finite element analysis of tool wear in machining
2008
Abstract The paper is focused on the 3D numerical prediction of tool wear in metal cutting operations. In particular, an analytical model, able to take into account the diffusive wear mechanism, was implemented through a specific subroutine. Furthermore, an advanced approach to model heat transfer phenomena at the tool–chip interface was included in the numerical simulation. The adopted simulation strategy gave the possibility to properly evaluate the tool wear. The 3D FEM results were compared with some experimental data obtained turning AISI 1045 steel using uncoated WC tool; a good agreement was found out.