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1 – 10 of over 29000This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder…
Abstract
This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.
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This paper gives a review of the finite element techniques (FE)applied in the area of material processing. The latest trends in metalforming, non‐metal forming and powder…
Abstract
This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming and powder metallurgy are briefly discussed. The range of applications of finite elements on the subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for the last five years, and more than 1100 references are listed.
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Sheet metal forming is a process of shaping thin sheets of metal by applying pressure through male or female dies or both. In most of used sheet‐formating processes the metal is…
Abstract
Sheet metal forming is a process of shaping thin sheets of metal by applying pressure through male or female dies or both. In most of used sheet‐formating processes the metal is subjected to primarily tensile or compressive stresses or both. During the last three decades considerable advances have been made in the applications of numerical techniques, especially the finite element methods, to analyze physical phenomena in the field of structural, solid and fluid mechanics as well as to simulate various processes in engineering. These methods are useful because one can use them to find out facts or study the processes in a way that no other tool can accomplish. Finite element methods applied to sheet metal forming are the subjects of this paper. The reason for writing this bibliography is to save time for readers looking for information dealing with sheet metal forming, not having an access to large databases or willingness to spend own time with uncertain information retrieval. This paper is organized into two parts. In the first one, each topic is handled and current trends in the application of finite element techniques are briefly mentioned. The second part, an Appendix, lists papers published in the open literature. More than 900 references to papers, conference proceedings and theses/dissertations dealing with subjects that were published in 1995‐2003 are listed.
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Da-Wei Zhang and He Yang
The purpose of this paper is to explore the basic loading state in local loading forming process of large-sized complicated rib-web component, which is important for understanding…
Abstract
Purpose
The purpose of this paper is to explore the basic loading state in local loading forming process of large-sized complicated rib-web component, which is important for understanding process characteristic, controlling metal flow and designing preformed geometry of the local loading forming process. Moreover the analytical models for different loading states are established to quickly predict the metal flow.
Design/methodology/approach
Through analysis of geometric characteristic of large-sized complicated rib-web component and the deformation characteristic on planes of metal flow by local loading method, a representative cross-section is put forward and designed, which could reflect the local loading forming characteristics of large-sized complicated rib-web component. Finite element method (FEM) is used to analyze the stress and metal flow, and the analytical models of metal flow are established by using slab method (SM).
Findings
Three local loading states and one whole loading state are found in the local loading forming process of representative cross-section. Further, four loading states also exist in local loading forming process of large-sized complicated rib-web components. With the metal distribution in the process, some local loading states may turn into whole loading state. For the representative cross-section, the relative error of metal distribution between SM and FEM results is less than 15 per cent, and the relative error of metal in the rib cavity between SM and FEM results is less than 10 per cent.
Originality/value
Metal flow can be controlled by adjusting the loading states in the process. According to the metal flow laws in different loading states, a simple unequal-thickness billet can be designed to achieve initial metal distribution, and then, the secondary metal distribution can be achieved in the process.
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Timo Schafer and Rolf Dieter Schraft
This paper aims to introduce a new incremental sheet metal‐forming process. By moving a hammering tool over a sheet of metal fixed in a frame, a three‐dimensional workpiece can be…
Abstract
Purpose
This paper aims to introduce a new incremental sheet metal‐forming process. By moving a hammering tool over a sheet of metal fixed in a frame, a three‐dimensional workpiece can be produced without using any special die plate.
Design/methodology/approach
This paper describes the exact procedure of the new process and the advantages in comparison with other flexible conventional and incremental forming processes. The hammering process in particular, will be considered with respect to material behavior and effects on the industrial robot. In addition, a special path generation for the incremental forming process and multiple robot tools with different drives constructed for the incremental forming process is shown.
Findings
During the research it was discovered that complex geometries can be produced without any die plate and that a hammering tool with a mechanical eccentric should be used for the incremental forming process.
Practical implications
As the forces on the handling equipment are very low compared with other forming processes, a common industrial robot can be used to move the hammering tool. Thus sheet metal parts can be produced with cost‐effective equipment. Mainly, small and medium‐sized enterprises can benefit from this new technology.
Originality/value
The incremental forming process presented in this paper is patented by the Fraunhofer Institute for Manufacturing Engineering and Automation. It is the first time that sheet metal parts with a size of 300×300 mm are formed by a hammering tool with 100 hits/s.
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Meelis Pohlak, Rein Küttner and Jüri Majak
To study the influence of process and product parameters on the properties of products in incremental sheet metal‐forming; to create models for process optimisation and to…
Abstract
Purpose
To study the influence of process and product parameters on the properties of products in incremental sheet metal‐forming; to create models for process optimisation and to introduce an approach to incremental forming process optimisation.
Design/methodology/approach
A new flexible sheet metal‐forming technique, incremental forming, has been studied. The technique can be viewed as a rapid prototyping/manufacturing technique for sheet metal parts. To analyse the process, an experimental study and finite element analysis were performed. For the optimal design of incremental forming process non‐linear mathematical programming was used. To estimate the limitations and main parameters of the process, a complex model was developed.
Findings
Introducing optimisation procedures for the incremental forming process allows users to increase productivity and to assure quality.
Research limitations/implications
As finite element analysis of the process is time‐consuming in real life situations, a future study should include creating analytical models for process modelling.
Practical implications
The described approach can be used in practice to improve competitiveness of companies producing sheet metal prototypes.
Originality/value
This paper offers guidelines for shortening processing time of sheet metal prototypes for engineers and researchers. The optimisation that is based on experimental/theoretical/numerical models of incremental forming process has not been covered before in the scientific literature.
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A number of oleochemicals have found application in the formulation of metal processing lubricants. Calcium palmitate can act as a gelling inhibitor for lubricants for non‐chip…
Abstract
A number of oleochemicals have found application in the formulation of metal processing lubricants. Calcium palmitate can act as a gelling inhibitor for lubricants for non‐chip metal forming, and diglyceryl oleate and sodium oleyl sulphate have been employed in chipless forming and machining lubricants. Glyceryl monooleate has been used together with paraffin wax and xylene for forming aluminium sheets, and isopropyl oleate has been blended into lubricants for cold forming of metal. Lubrication in cold forming of steel and aluminium alloys has been promoted by the use of sodium stearate and phosphating processes. Stearic acid has also been utlized in metal forming. Butyl butanamine stearamide is applicable in lubricants for non‐ferrous metal working, and coatings that can prevent galling when titanium is cold worked can be formed on the metal by the use of 0.5 grams of hydrofluoric acid, with 10 grams stearic acid in 100 ml. of a solvent, the process being accelerated by the inclusion of phosphoric acid at 0.85 grams. Calcium stearate has also been used in solvent‐based metalworking Iubricants, in acrylic electrophoretic lubricant coatings on metal, and in bentonite‐containing metalworking oils. Mixtures of cetyl alcohol and tricresyl phosphate have been cast into slabs and used on metalworking tools.
Hulusi Delibaş and Necdet Geren
The purpose of this study is to produce a low-cost sheet metal forming mold made from the low melting point Bi58Sn42 (bismuth) alloy by using an open-source desktop-type material…
Abstract
Purpose
The purpose of this study is to produce a low-cost sheet metal forming mold made from the low melting point Bi58Sn42 (bismuth) alloy by using an open-source desktop-type material extrusion additive manufacturing system and to evaluate the performance of the additively manufactured mold for low volume sheet metal forming. Thus, it was aimed to develop a fast and inexpensive die tooling methodology for low-volume batch production.
Design/methodology/approach
Initially, the three-dimensional printing experiments were performed to produce the sheet metal forming mold. The encountered problems during the performed three-dimensional printing experiments were analyzed. Accordingly, both tunings in process parameters (extrusion temperature, extrusion multiplier, printing speed, infill percentage, etc.) and customizations on the extruder head of the available material extrusion additive manufacturing system were made to print the Bi58Sn42 alloy properly. Subsequently, the performance of the additively manufactured mold was evaluated according to the dimensional change that occurred on it during the performed pressing operations.
Findings
Results showed that the additively manufactured mold was rigid enough and proved to have sufficient strength in sheet metal forming operations for low-volume production.
Originality/value
Alternative mold production was carried out using open-source material extrusion system for low volume sheet metal part production. Thus, cost effective solution was presented for agile manufacturing.
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Xuewei Fang, Zhengying Wei, Jun Du, Lu Bingheng, Pengfei He, Bowen Wang, Jian Chen and Ruwei Geng
This paper aimed to propose a novel fused-coating-based additive manufacturing (FCAM); the study of key process parameters and mechanical tests are performed to determine the…
Abstract
Purpose
This paper aimed to propose a novel fused-coating-based additive manufacturing (FCAM); the study of key process parameters and mechanical tests are performed to determine the proper parameters when building metal components.
Design/methodology/approach
Sn63Pb37 alloy is deposited in an induction heating furnace with a fused-coating nozzle to build metal parts on a copper-clad substrate. The process parameters including nozzle pressure, nozzle and substrate temperature and nozzle gap between substrate are analyzed and found to have great influence on parts quality. The mechanical property tests between the fused-coating and casting parts are performed in horizontal and vertical directions. Also, the optical microscopy images are used to ascertain under which conditions good bonding can be achieved.
Findings
A FCAM method is proposed, and the exploration study about the manufacturing process is carried out. The critical parameters are analyzed, and microscopy images prove the suitable temperature range that requires to fabricate metal parts. The mechanical tests confirm that tensile strength of printing parts is improved by 20.4 and 11.9 per cent in horizontal and vertical direction than casting parts. The experimental results indicate that there is a close relationship between process parameters and mechanical properties.
Originality/value
This paper proves that FCAM provides an alternative way to quickly make functional metal parts with good quality and flexibility compared with other additive manufacturing methods. Moreover, good mechanical property is achieved than conventional casting parts.
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Studere Corrosion has been described as a transformation process in which a metal passes from its elementary form to a combined condition. It includes wet and dry corrosion; the…
Abstract
Studere Corrosion has been described as a transformation process in which a metal passes from its elementary form to a combined condition. It includes wet and dry corrosion; the former requires an aqueous environment and the latter is oxidation. Deterioration of the metal due to physical causes is not called corrosion, but is known as erosion, galling, wear, etc, depending upon the material and the conditions. Corrosion is the result of the metal chemical or an electrochemical reaction with its environment. Sometimes the chemical reaction is accompanied by physical deterioration, as in fretting corrosion. It should be noted here that the term corrosion is only applied to metals; non‐metals rot, crack or erode. Also it should be appreciated that only ferrous metals can ‘rust’, i.e. form hydrous ferric oxides.