Flexible metal forming processes are novel ways to meet the growing needs for maintaining economic feasibility in mass production and customization. The flexible forming processes inherently have ...more process parameters to control than conventional processes, and thus they may be less economical. However, owing to the rapid development of computing technology over the last two decades, the numerical simulation approach has gained significant attention for optimizing the process parameters. Based on the numerical analysis, sophisticated theories have also been developed to describe the material deformation characteristics during forming processes. In this paper, incremental sheet metal forming, incremental bulk forming, and flexible roll forming are briefly overviewed with regard to innovative techniques for numerical simulations of various flexible metal forming processes.
Flexibility in metal forming Yang, D.Y.; Bambach, M.; Cao, J. ...
CIRP annals,
2018, 2018-00-00, Letnik:
67, Številka:
2
Journal Article
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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.
We study, experimentally and theoretically, the mechanical response of sheet materials on which line cracks or cuts are arranged in a simple pattern. Such sheet materials, often called kirigami (the ...Japanese words, kiri and gami, stand for cut and paper, respectively), demonstrate a unique mechanical response promising for various engineering applications such as stretchable batteries: kirigami sheets possess a mechanical regime in which sheets are highly stretchable and very soft compared with the original sheets without line cracks, by virtue of out-of-plane deformation. However, this regime starts after a transition from an initial stiff regime governed by in-plane deformation. In other words, the softness of the kirigami structure emerges as a result of a transition from the two-dimensional to three-dimensional deformation, i.e., from stretching to bending. We clarify the physical origins of the transition and mechanical regimes, which are revealed to be governed by simple scaling laws. The results could be useful for controlling and designing the mechanical response of sheet materials including cell sheets for medical regeneration and relevant to the development of materials with tunable stiffness and mechanical force sensors.
Metal forming is not only shaping the form of a product, it is also influencing its mechanical and physical properties over its entire volume. Advanced analysis methods recently enable accurate ...prediction of these properties and allow for setting these properties deterministically during the forming process. Effective measurement methods ensure the setting of these predicted properties. Several real examples demonstrate the impressive achievements and indicate the necessity of a paradigm change in designing products by including manufacturing-induced effects in the initial dimensioning. This paradigm change will lead to lightweight components and serve environmentally benign designs.
Metal forming process is one of the oldest manufacturing techniques. It has witnessed the shift from conventional to integration of smart systems for manufacturing of highly complex components. Many ...mathematical, experimental and simulation software techniques are discussed. Servo press is the most indispensable machine used for the manufacturing of delicate parts of automobile, aviation industry with high accuracy. The main motive of replacing or modifying the prevailing conventional manufacturing techniques into modern, smart and sustainable manufacturing like industry 4.0 is to become more competitive and to adopt customization & sustainability. Integration of industrial internet of things (IIoT) with automated supply chain has given optimized productivity, quality, and economical feasibility. This manuscript throws some light on different metal forming process, servo press application in automobile, aviation industry and different components require to make metal forming smart and sustainable in term of industry 4.0.
Hot rolling is one of the most widely used hot metal forming processes by shaping the hot workpiece with cylindrical rolls. Its harsh working conditions, including high loading (up to 0.5 GPa), ...elevated temperature (600–1100 °C) and high speed (above 10 m/s), lead to the problems of high friction, severe wear, oxidation at the tool/workpiece rubbing surfaces. Lubricants are essential to reduce the rolling force, prolong the service life of work rolls, and improve overall process efficiency. In this work, the mixture of sodium polyphosphate and nano-TiO2 as water-based hot rolling lubricants were studied using a laboratory hot rolling mill. Aqueous lubricant with 2 wt.% TiO2 in 20 wt.% sodium polyphosphate demonstrates an excellent lubrication performance with a reduction of a rolling force of 10% compared to pure water lubrication condition. The sodium polyphosphate can not only act as a surfactant to improve the dispersibility of TiO2 nanoparticles in water, but also form an easily sheared glass melt at high temperature to lubricate the workpiece/roller. Focused ion beam and transmission electron microscope analysis of the sliding interface demonstrate that some nano-TiO2 were contained in the polyphosphate melt. The concept that combines the inorganic polymer with nanoparticles to produce the synergy effects of glass lubrication and nanoparticle lubrication can provide new insight into the design of lubricants for the hot metal forming process.
•Water-based lubricant with a mixture of sodium polyphosphate and nano-TiO2 for hot rolling process was studied.•Sodium polyphosphate can act as a surfactant to improve the dispersibility of TiO2 NPs, and lubricate the strips/roller.•Aqueous lubricant with 2 wt.% TiO2 in 20 wt.% sodium polyphosphate demonstrates an excellent lubrication performance.•The synergy effects of glass lubrication and nanoparticle lubrication can be extended to other hot metal forming process.
The energy demand and CO2 emissions of the steel processing industry are a global challenge. During conventional steel processing, the treatment of iron ore and steel in a molten state heavily ...contributes to this problem. This paper provides an in-depth investigation of the benefits and technical requirements of an alternative processing pathway with minimal energy and CO2 burdens. Our proposed method, scrap metal consolidation (SMC) by rolling, is adapted from roll bonding, a scalable metal bonding technique, commonly used for niche composite applications to achieve material properties unattainable by monolithic alloy design. SMC transforms steel scrap into hot rolled steel in solid state without melting. Based on pre-published high-fidelity industrial data, we determined that processing hot rolled steel from scrap in the solid state would consume 94% less energy compared to the primary steel processing route with 94% less CO2 burden. Compared to conventional recycling methods, the energy savings of SMC would be 86%, with an 84% decrease in CO2 emissions. The proposed method is described in detail, and the process windows for AISI 1008 mild steel and SS304 stainless steel were determined in terms of rolling temperature and reduction using a lab-scale rolling mill at a temperature range of 700–1100 °C. The formability of the consolidated mild steel is also evaluated via the hemisphere punch test, a standard industrial test for assessing the formability of sheet metals. While the fracture height of consolidated specimens is in the 9.27–10.62 mm range, the monolithic sample has a fracture height of 10.34 mm. The test results show that the consolidated sheets have comparable formability to monolithic specimens. These investigations altogether demonstrate that SMC-by-rolling is a feasible and environmentally sustainable alternative for conventional steelmaking or recycling processes.
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•Solid-state consolidation of steel scrap uses 94% less energy than primary processing.•Compared to recycling, scrap metal consolidation saves 84% of process CO2 emissions.•Process boundaries for mild and stainless steel follow a reverse S-curve trend.•Test results exhibit comparable formability for roll-bonded and monolithic samples.•Most sheet metal forming operations don't cause opening stress, reducing failure risk.
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•Weakening the strong basal texture produced by extrusion.•It can achieve significant shear-compression deformation with large strain.•The physical simulation under different strain ...rate ranges can be satisfied.•The ideal thermal deformation parameters for pure Mg can be predicted.
In this study, the deformation behavior and microstructure evolution of pure Mg under hot shear-compression deformation conditions are investigated using the “Shear-Compression Specimen” as a model, which provides theoretical guidance for the investigation of the principles of surface defects in the hot extrusion process. The results showed low flow stress corresponded to a high temperature and a low strain rate, temperatures between 350–450 °C and strain rate at 5 s−1 are the perfect hot deformation parameters. The deformation generates a special texture that is bent by 45° along the extrusion direction, weakening the strong basal texture structure created by extrusion. The deformed microstructure is fine and uniformly distributed. In summary, the surface of the material is forced to undergo a complex shear-compression deformation during the hot extrusion process, while the core belongs to a simple uniaxial extrusion deformation. In some specific deformation conditions, the difference between these two may produce some defects.
Lightweight sheet metals are attractive for aerospace and automotive applications due to their exceptional properties, such as low density and high strength. Sheet metal forming (SMF) is a key ...technology to manufacturing lightweight thin-walled complex-shaped components. With the development of SMF, numerical simulation and theoretical modelling are promoted to enhance the performance of new SMF technologies. Thus, it is extraordinarily valuable to present a comprehensive review of historical development in SMF followed by state-of-the-art advanced characterization and modelling approaches for lightweight metallic materials. First, the importance of lightweight materials and their relationship with SMF followed by the historical development of SMF are reviewed. Then, the progress of advanced finite element technologies for simulating metal forming with lightweight alloys is covered. The constitutive modelling of lightweight alloys with an explanation of state-of-the-art advanced characterization to identify the constitutive parameters are presented. Then, the formability of sheet metals with major influencing factors, the techniques for measuring surface strains in SMF and the experimental and modelling approaches for determining the formability limits are clarified. Finally, the review is concluded by affording discussion of the present and future trends which may be used in SMF for lightweight metallic materials.
Due to the change from mass production to mass personalized production and the resulting intrinsic product flexibility, the automotive industry, among others, is looking for cost-efficient and ...resource-saving production methods to combining global just-in-time production. In addition to geometric manufacturing flexibility, additive manufacturing offers a resource-saving application for rapid prototyping and small series in predevelopment. In this study, the FDM process is utilized to manufacture the tooling to draw a small series of sheet metal parts in combination with the rubber pad forming process. Therefore, a variety of common AM polymer materials (PETG, PLA, and ABS) is compared in compression tests, from which PLA is selected to be applied as sheet metal forming die. For the rubber pad forming process, relevant processing parameters, i.e., press force and rubber cushion hardness, are studied with respect to forming depth. The product batch is examined by optical evaluation using a metrological system. The scans of the tool and sheet metal parts confirm the mechanical integrity of the additively manufactured die from polymer and thus the suitability of this approach for small series in sheet metal drawing processes, e.g., for automotive applications.
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