مقاله انگلیسی رایگان در مورد انعطاف پذیری در شکل دادن به فلز – الزویر 2018

Flexibility in metal forming is needed more than ever before due to rapidly changing customer demands. It paves the way for a better control of uncertainties in development and application of metal forming processes. Although flexibility has been pursued from various viewpoints in terms of machines, material, process, working environment and properties, etc., a thorough study of the concept was undertaken in order to with problems of manufacturing competiveness and tackle new challenges of manufacturing surroundings. Therefore, in this paper, flexibility in forming is reviewed from the viewpoints of process, material, manufacturing environment, new process combinations and machine–system–software interactions.

Introduction

Background and motivation

The manufacturing sector undergoes drastic changes in the global scale due to the advent of a new industrial revolution, the so-called fourth industrial revolution or Industry 4.0 [170]. A key feature of this revolution is the increasing interaction of human beings, production machines and products. As a consequence, conventional mass production is changing gradually towards manufacturing systems for mass customization, with higher flexibility and on-demand manufacturing, which brings about new technological challenges. Such a new industrial wave demands connectivity, automation and intelligent systems, in mass customization and on-demand manufacturing in addition to mass production as summarized in Fig. 1 [184]. The mentioned connectivity and intelligentization enable realization of automated manufacturing of products and related automated services. The pursuit of these three factors would finally lead to super-connection and super-intelligentization of human beings, things and space, and ultimately resulting in systemic innovation of industry and society. While flexibility is inherent to manufacturing processes such as machining and welding, die-based manufacturing processes such as metal forming and casting are increasingly challenged to meet the demands on flexibility. A working group study on mega-trends and the future of metal forming [127] in 2012 revealed the importance of flexibility. Theresults of the study were summarized as shown in Fig. 2. Various areas, including flexibilitization, intelligent processes, complexity of shape and integration of functions, all of which demand for flexibility of forming either directly or indirectly. 3D printing of metals was included as a separate category, though not having been included in traditional forming, but it becomes a very powerful means of highly flexible manufacturing for producing metallic parts and dies with reasonable productivity for some industrial manufacturing sectors. Flexibility of metal forming has become an important issue in recent manufacturing demands and plays an essential role in customized mass and individualized production in the manufacturing industry. As flexible sheet metal forming, single point incremental forming has been widely employed and subject to extensive research [61,73]. The introduction of double point (sided) incremental forming had enhanced the formability and extended the range of shape complexity [125,199]. The combination of incremental forming and conventional sheet forming processes further extended the capability of incremental forming with additional advantages including increased productivity [13]. Incremental bulk metal forming has a long history since the Bronze age. Since then, incremental bulk forming has been developed by employing various forming processes including forging typically and many incremental forming processes using rotating tools such as flow forming, rotary swaging, orbital forming, gear rolling, pierce rolling and ring rolling, etc. [52]. Various flexible forming processes for both sheet and bulk can be found in Japan and they are well summarized in Ref. [8]. Incremental forming is surely the key flexible forming process and has been diversified for manufacturing various metallic products. However, flexibility in forming has been pursued from diverse viewpoints in terms of complexity, material, process, working environment and machine, etc. In this work, flexibility is newly viewed and subjected to review from various angles of perspective in order to provide new prospects of flexibility in metal forming.