Komal Rade

“Flexible

Sheet Metal Forming”

Seminar Submitted to KAVAYITRI BAHINABAI CHAUDHARI NORTH MAHARASHTRA UNIVERSITY, JALGAON. in fulfillment of requirement for the award of degree of

BACHELOR OF ENGINEERING Under the

Faculty of Engineering and Technology In the discipline

Mechanical Engineering

By KOMAL RADE B.E. Computer

Guided By Prof. V S Chavan Asst. Professor

Department of Mechanical Engineering Godavari Foundation’s

Godavari College of Engineering, Jalgaon ( An affiliated to Kavayitri Bahinabai Chaudhari North Maharashtra University, Jalgaon.) October 2018

Godavari Foundation’s

Godavari College of Engineering, Jalgaon (An affiliated to Kavayitri Bahinabai Chaudhari North Maharashtra University, Jalgaon)

CERTIFICATE This is to certify that the Case Study titled, “ FLEXIBILE SHEET METAL FORMING” submitted by KOMAL RADE in fulfillment of the degree of BACHELORS OF ENGINEERING in the Department of MECHANICAL ENGINEERING, Godavari College of engineering, North Maharashtra University, Jalgaon is a bonafide record of work carried out by him in the Department of Computer Engineering, North Maharashtra University, Jalgaon under my guidance and supervision. In my opinion this work has attained the standard fulfilling the requirements of the regulations of the University. Date: Place: Jalgaon

Prof. V S Chavan Asst. Professor

Prof. Vijay Patil H.O.D, Mechanical Department

Dr. V.G.Arajpure Principal

DECLARATION / UNDERTAKING

I hereby declare that the work presented in this project “ FLEXIBLE SHEET METAL FORMING ” was carried out by me under the supervision of guide from July to October - 2018 This work or any part of this work is based on original research and has not been submitted by me to any University/Institution for the award of any degree.

Date: Place: Jalgaon Komal Rade Student, T.E. Mechanical

ACKNOWLEDGEMENT

No work can be accomplished unless it has evolved as a result of cooperating, assistance and understanding of some knowledgeable group of people. I take the opportunity to thank our Principal Prof. Dr. V.G. Arajpure and Head of Department Prof. Vijay Patil for providing all the necessary facilities, which were indispensable in the completion of special study. I would like to thank my guide Prof. V. S. Chavan for providing to be a great help by giving us guidance through their vast experience, intellectual skills and also thankful to all the staff members of the Computer Engineering Department. I would also like to thank the college for providing the required magazines, books and access to the internet for collecting information related to the report. Finally, I would like to thank my parents.

Komal Rade Student, T.E. Mechanical

Abstract In general, this exible forming process using the recon gurable die has been utilized for manufacturing of curved thick plates used for hull structures, architectural structures and so on. In this study sheet metal forming process is carried out by using exible dies model instead of conventional matched die set.. In the exible forming process for sheet metal, e ect of a blank holder is also investigated according to blank holding methods. Formability in view of occurrence of dimples is compared with regard to the various punch sizes. Consequently, it is con rmed that the exible forming for sheet material using rubber pad has enough capability and feasibility for manufacturing of smoothly curved surface instead of conventional die forming method. Flexible forming systems have been used e ciently in metal removal applications. Recently it became evident, however, that a true economic ad-vantage of exible forming will become available only when an integration between forming, cutting, and other operations will be materialized. Flexible forming is a sheet metal forming process with the application of soft material tooling. In this study, exible (silicone rubber, SR, and styrene butadiene rubber, SBR) and semi-rigid (polyamide 66, PA) polymeric materials were adopted to make several upper dies which were used in combination with aluminium lower dies. In response to the high cost and long cycle in the die design and manufacture, this paper explores , exible forming system of sheet metal based on the fundamental principle of Multi-Point Forming. The selected future directions of development in new technologies and machines for sheet metal forming taking into account modern blank holding systems in the process of deep drawing have been indicated. Also the tendencies in introduction of new technologies and modernization of presently used technologies in order to increase productivity have been discussed. In the eld of sheet forming, innovative and exible processes that do not impose the use of expensive conventional equipments and they are do not require time consuming set-up operations have become, nowadays, a rather promising research topic. Two di erent main lines are currently followed: the former is based on the development of new strapping processes based on the utilization of exible media, while the latter is

aimed to develop so called progressive forming processes (spinning and incremental forming). In this topics embedded are assigned to di erent research groups and are presented below.

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Contents List of Figures

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1 Introduction

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2 Literature Survey

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3 Methodology

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4 CLASSICATIONS 4.1 Multipoint Incremental forming . . . . . . . . . . . . . . . . . . . . . 4.2 Flexible Multipoint Hydroforming (Deep Drawing) . . . . . . . . . . 4.3 Microscale Laser Forming . . . . . . . . . . . . . . . . . . . . . . . .

8 8 11 16

5 Advantages of Flexible Forming Over Convectional Forming

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6 Disadvantages of Flexible Forming Over Convectional Forming

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7 Applicatons

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8 Future Scope

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9 Conclusions

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References

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List of Figures 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9

Principle of Multipoint Forming . . . . . . . . . . . . . . . . . . . . . Multipoint Stretch forming . . . . . . . . . . . . . . . . . . . . . . . . multi-point exible forming . . . . . . . . . . . . . . . . . . . . . . . The Experimental Apparatus . . . . . . . . . . . . . . . . . . . . . . Forming technique with positive initial gap . . . . . . . . . . . . . . . Forming technique with negative initial gap . . . . . . . . . . . . . . Multipoint Incremental forming . . . . . . . . . . . . . . . . . . . . . The schematic Representation Of Flexoforming . . . . . . . . . . . . microscale Laser Forming . . . . . . . . . . . . . . . . . . . . . . . . .

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9 9 11 12 13 14 14 15 16

Chapter 1 Introduction Flexible forming processes allow for the adaptation and modi cation of the prod-uct geometry with little e ort. They enable the economical production of prototypes and small series, an extended geometry portfolio and the production of thickness-optimized semi- nished products. Therefore they are serving lightweight design and the trend towards shorter product development cycles as well as increasingly indi-vidualized products. Many application parts contain elements which are made by anging or hole anging operations. The production of these anging elements by means of Incremental Sheet Forming, short ISF, can be easily integrated into the production process on the Flexible Sheet Metal Processing Centre. Thus, the entire process chain of the component production can be carried out in the same clamping. The advantages of this process integration are demonstrated by a component based on the inspection cover of the Airbus A320. First of all, the curved preform of the target geometry is created within a very short period of time by stretch forming. In ISF, a hemispherical forming tool successively forms the remaining areas of the component. After trimming, the high process limits of ISF are nally used to set up the ange and hole ange elements. Sheet metal forming processes are widely used to produce complex parts, and consist of a series of basic operations, like bending, stretching, stamping and blanking. Among sheet metal forming, exible forming is a new process for the production of sheet metal parts with complex shapes by using a exible medium, such as rubber, as a die. Recently, rubber forming processes have 1

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gained interest since they have been used extensively in the aircraft industry. The advantages of exible forming over conventional forming processes are principally low cost tooling, versatility of the process, and low damaging of the formed parts. In this way, the development of innovative technologies within manufacturing is highly requested. In particular, as far as forming processes are concerned, innovative processes that do not impose the use of expensive conventional equipments and they do not require time consuming setup operations have become, nowadays, a rather promising research eld. In fact, such technologies give rise to exibility improvement in manufacturing processes, and, as a consequence, enable a competi-tive advantage for industries in the modern manufacturing environment. With the rapid development of reduction in size and integration, micro components have been widely applied to micro-electromechanical systems, micro-system technology, and precision machinery. Responding to this important industry trend, micro forming processes, which have unique advantages compared with other micro manufacturing technologies, have been rapidly developed and researched.

Nevertheless, the deformation behavior of materials is considerably changed when the geometrical sizes of components decrease to the micro scale. The defor-mation mechanics, material ow, and friction condition are changed because of the size e ect In the last few years the metal forming eld have been involved in several research projects both on hydroforming and on incremental forming. Both hydro-forming and incremental forming permits a very relevant reduction of the tooling and set-up costs and improves process exibility; on the other band they are quite "young" and under development processes, which require a considerable research e ort.

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Chapter 2 Literature Survey 1. Huixia Liu 1,*, Wenhao Zhang et. al ; Multilayer metal composite sheets possess superior properties to monolithic metal sheets, and formability is different from monolithic metal sheets. In this research, the feature size e ect on formability of multilayer metal composite sheets under micro scale laser exible forming was studied by experiment. The research results showed that the formability of two-layer copper/nickel composite sheets was strongly in uenced by feature size. With feature size increasing, the e ect of layer stacking sequence on forming depth, thickness thinning ratio, and surface roughness became increasingly larger. However, the normalized forming depth, thickness thinning ratio, surface roughness, and micro-hardness of the formed compo-nents under the same layer stacking sequence rst increased and then decreased with increasing feature size. As such, it is critical to investigate the size e ect on the deformation behavior of materials. 2. Liu, H.X.; Sun, X.Q. et. al ;The process of exible hydroforming is a combination between the hydroforming and the multipoint exible forming, which allows a synergy of the advantages of two processes. On one hand, the hydro-forming process allows a contribution in the exibility by replacing one of two shaping tools by a uid, on the other hand, the multipoint exible forming, allows modifying freely the nal shape with its recon gurable tool, constituted

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by a matrices of adjustable punch elements. 3. Peng-yi Wang, Hui Song et. al ;To protect the limited natural resources and solve the global environmental problems, lightweight constructions have received great attention. More exible forming technologies are needed for its help on lightweight constructions. They are invented a new process to draw sheet metal blanks into a die utilizing a owing viscous thermoplastic poly-mer medium. The method was later named viscous pressure forming (VPF), which use a ow able semi-solid polymer with a certain viscosity and strain rate sensitivity as a forming medium In VPF, it is possible to choose viscous medium with certain viscosity according to the geometries and material features of formed parts. There are also optimum viscosities for di erent stages in a forming process. But it is di cult to change the medium viscosity dur-ing a single process in VPF. It will have great signi cance to develop a new exibledie forming approach, which can adjust the viscosity of medium during a signal forming process. . 4. Mao, T., and Altan, et. al ; In order to changes associated with construc-tion of machines used in die and Die-less sheet metal forming have been presented. The selected future directions of development in new technologies and machines for sheet metal forming taking into account modern blank holding systems in the process of deep drawing have been indicated. Also the tenden-cies in introduction of new technologies and modernization of presently used technologies in order to increase productivity. 5. Tisza, M. et. al ; To keep this key role of sheet metal forming in manufacturing industry, a continuous development is necessary concerning the materials, the development of new innovative forming processes, the tooling and manufacturing equipment. The ever-increasing requirements stated by the automotive industry may be regarded as one of the main driving forces behind sheet-metalforming innovations. Some decades ago, design engineers mainly focused their attention on structural and dimensional stability and durability. In recent GF’s Godavari College of Engineering, Jalgaon

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years, the reduction of fuel consumption together with increasing comfort re-quirements led to the intensive development of innovative new materials. En-hanced sti ness together with weight reduction resulted in the development and wide application of various grades of high-strength steels. Nowadays, several micro-alloyed and phosphorous alloyed steels both with and without bake-hardening are frequently used.

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Chapter 3 Methodology To elaborate new, innovative sheet-forming processes, the automotive industry always played a key role in Metal forming had its beginnings in the latter part of the 19th century (Thiruvarudchelvan, 1993). In this review on elastomers in metal forming, Thiruvarudchelvan individuated several processes: the Guerin process (which used an enclosed rubber pad); the Marform process (with the addition of an independent blank-holder); the Verson- Wheelon process (which used a comparatively lighter press with an in atable rubber bag); bending, roll forming; blanking and piercing; embossing; deep drawing; free forming; tube bulging. In this review, urethanes were considered the best materials for exible tools because of their good oil and solvent resistance, good wear resistance, high thermal stability and load bearing capacity. In 1995, Browne and Battikha studied the aluminium sheet forming (by Guerin process and Marform process) using a exible die made of neoprene or commercial rubber (Browne and Battikha). They concluded that exible forming is capable of producing, from thin aluminium alloy sheet, shallow formed parts with good surface nish and little metal thinning. Tooling costs are reduced considerably as only one form block needs to be manufactured per component. Also the time to production is low because of the system simplicity which enables the rapid production of Prototype parts. In a last contribution, the application of prototyping techniques like stereolithography was discussed for the production of exible tools in polyurethane Despite of the big interest in this technology, scanty information are 6

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available in the scienti c literature about exible forming. Many important aspects have not been deepened yet such as the e ect of the viscoelatic behaviour of the tool exible material on the process performances, or the durability of the exible tool. Moreover, even if new high performance materials have been introduced into the market in the last decade, their suitability for rubber forming has not been evaluated. The most famous and common manufacturing process in many industrial and civil sectors is sheet metal forming which are capable of producing good quality complex part with nowadays technology. However, the demand of the customers could have e ects on many conventional forming methods when small production batch with high product quality are required. With economic competitiveness, manufac-turing companies must nd new solutions that are more exible to satisfy di erent market segments. In most of the manufacturing processes, prototyping is a very important step before beginning real operation in mass production. Prototype al-lows the improvement and development of the product, changing its design in early steps of product development. Producing prototypes in some manufacturing pro-cesses may consume a lot of money and time to tryout, especially if speci c dies are required as it is the case of sheet metal components. Nowadays, formability issues of tailor-welded blanks are one of the most important questions, to provide signi cant load-bearing parts with reduced weight without any decrease in shape or structural stability. Recently, whole process chains were developed to further improve the suitability of light-weight structures. The whole process includes strip production with exible rolling (the resulting sheet is often termed as tailor-rolled blank), and subsequent manufacturing of pro le-shaped structural elements with pro le bending forming processes. Light-weight structural elements produced by this process have less weight than any other comparable structures made from constant initial material thickness, and at the same time they have much better structural behaviour. Among new, innovative forming processes hydroforming can be regarded as an outstanding one. Hydroforming is mainly used to produce hollow sheet or tube products often with complicated geometry to produce light-weight parts more economically. GF’s Godavari College of Engineering, Jalgaon

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Chapter 4 CLASSICATIONS They are classi ed in three groups 1. Multipoint Incremental forming 2. Flexible multipoint Hydroforming (deep drawing) 3. Micro scale Laser Forming

4.1

Multipoint Incremental forming

Multi-point forming g. multi-point die forming (MPDF) or multipoint press forming (MPPF) technology is a exible 3D manufacturing process for varied large sheet which similar to forming process of solid dies. In Solid die, two opposite solid die (upper and lower) are used to press onto a blank and form into particular shapes. Instead, MPF used matrix punches with speci c shape that could adjust height by mean of line actuator . Due to the rapid change of two element group, several special MPF techniques that are impossible in conventional forming have been investigated. For instance, spring-back is compensated cycle by cycle, large deformation could be obtained and large size of sheet can be formed in small scale MPF equipment.

MPF is to use the adjustable element group to form the variable curved surface, taking place of the traditional die forming. It is a exible method that can be used in forming 3-D surface of sheet metal. The essence of MPF is to divide the 8

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Figure 4.1: Principle of Multipoint Forming

curved surface of the die into many discrete pins, each pin called element, with the element group instead of the traditional dies (Fig. I). By this means, a set of this apparatus can be used to carry out di erent curved surface forming by adjusting the elements height of both the upper side and the lower side. That is to say, the basic conception of MPF is using the elements group to shape the surface of the die. Each element can be controlled by computer so that the curved surface can be changed at any time. Based on the principles of MPF and deforming characters, MPF is divided into four di erent types - multi-point die forming, multi point half die forming, multi point press forming, and multi point half press forming.

Figure 4.2: Multipoint Stretch forming

Overcoming mass production problems following try-out, new press technologies continuously emerge as new techniques and ideas in sheet metal forming are considered in press design. Controlling the ow of sheet metal via controllable multicylinder blank holder actuators reduces die-try out time by cutting down on die work . The application of multi-input multi-output (MIMO) stamping process controller GF’s Godavari College of Engineering, Jalgaon

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especially in case of forming complex-geometry parts allows to apply the non-uniform metal in di erent regions of the draw piece. The multi-point exible forming (MPF) is another recent exible technique for manufacturing three-dimensional sheet metal parts. In this process, the sheet metal can be formed between a pair of opposed matrices of punch elements instead of the conventional xed shape die sets. The punches elements are controlled simply, by adjusting the height of the elements of both upper and the lower matrices, di erent curved surfaces can be created. By using this tech-neology, production of many parts with di erent geometry will be possible just by using one same die set and the need to design and manufacturing of various die will be avoided that lead to great saving in time and manufacturing cost specially in the eld of small batch or single production. a production of lighter structures and complex forms. However, in exible multipoint processes, the direct contact between the blank and punch elements generates a severe dimpling on the nal part, the insertion of an elastomeric sheet, between the dies and the blank as seen in ( gure1) , has been an e ective by playing on the sti ness and the thick-ness of an elastomeric sheet, it was possible then to reduce in a signi cant way these dim-

pling severity.

Multipoint sandwich

exible forming (MPSF) is an innovative

version of the multipoint process which consist to substitute the movable die by a stack of elastomeric sheets, un-der the slide of the press ( gure 2)but it is often necessary to adapt the shape of this stack to the depth of the part to be produced. The multipoint exible hydroforming is an original process which combines the hydroforming and the multipoint exible forming, to obtain a synergy of the advantages of both processes. It allows to keep the whole exibility of the basic multipoint exible forming (with two multipoint discrete dies), by using uniquely at one side, of a single multipoint discrete die to perform completely the nal part shape, on the other side of the blank, the second multipoint die is advantageously substituted by the uid pressure, which can be applied, if necessary, via an elastomeric membrane.

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Figure 4.3: multi-point

4.2

exible forming

Flexible Multipoint Hydroforming (Deep Drawing)

The application of sheet hydro-forming in the modern automotive industry has bad a very large increase in the last decade. It is worth pointing out some of the most relevant advantages o ered by sheet hydro-forming. This technology allows to strongly reducing both the costs due to the manufacturing and the maintenance of the dies and the ones linked to set-up times. Such reduction is not only due to the avoidance of one of the dies; furthermore the pressure distribution due to the uid action over the sheet is more gradual and distributed, thus permitting to construct the remaining die in less expensive materials than the conventional ones. Other advantages supplied by hydroforming are a remarkable increase of the limiting drawing ratio in deep drawing, a more uniform thickness distribution on the stamped sheet, a safer residual stresses distribution and nally a better surface quality than using other traditional processes. The rubber material used for the exible die is

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characterized by a nonlinear stress-strain relation for large deformation, as well as it is nearly incompressible through the volumetric compression test. Therefore, the Mooney-Rivlin hyperelastic model can be presented to describe this behavior.

Figure 4.4: The Experimental Apparatus

The special experimental set up shown in Figure 4 was developed to conduct micro deep drawing experiments. In general, this device consists of two main component sets. The rst set, which represents the upper movable part of the device, is composed of two groups of components the rst group involves upper plate, three springs, three spring guiders, three guide posts, solid punch and lower plate. The second one involves the main tools responsible directly of the micro deep drawing operation, which are blank holder, blank holder house, xing ring and holding spring. This set is driven by the movable grip of the Instron 3956 machine, where the load and displacement can be acquired directly from the Bluehill software provided with this machine. The second set is constructed of a solid base, rubber container and rubber pad. The main function of the three springs is to keep the ange portion of the blank holder in direct contact with rubber container surface during the drawing stroke. Therefore, these springs have a relatively high sti ness of 300 N/mm, which is enough to overcome any possible movement of the middle plate upward.

Working procedure The forming procedure, shown in Figure 5, is carried out with a positive initial gap and can be summarized in the following steps: Step 1: The rigid punch is moved downward just to contact the blank surface. Step 2: In this step the punch deform GF’s Godavari College of Engineering, Jalgaon

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Figure 4.5: Forming technique with positive initial gap

both the blank and rubber pad just through the initial gap adopted. As a result of incompressibility of the rubber material, a hydrostatic pressure will be generated in the rubber pad keeping the formed part of the blank in continuous contact with the rigid punch. Since the rubber pad is restrained inside a closed cylindrical space the resulting pressure pushes both the blank ange and blank holder upwards through the gap against the holding spring. Through this step the contact area between the blank ange and the holder decreases causing the holding force to decrease. As a result, the compromise between the decreasing contact area and the increasing rubber pressure is a very important aspect in this technique. Step 3: The nal step of the drawing operation starts just when the blank holder reaches the xing plate. At this moment the rubber container is completely closed a high forming load is needed to resist the high reaction pressure of the rubber pad. Afterwards, the rigid punch is kept moving down to nish drawing stroke. In some cases where an initial compression is required to be established the experimental procedure illustrated in Figure (6) is utilized. Step 1: The rigid punch is moved downward just to contact the blank surface. Step 2: All of the rigid punch, blank holder and xing plate are moved downward for the required initial compression distance (negative gap). This technique generates an initial pressure (pre-bulging pressure) in the rubber pad. Step 3: In this step both the blank and the rubber are formed by the rigid punch, producing a complete cup. An important note here is that the incremental increase in the forming load in this technique is GF’s Godavari College of Engineering, Jalgaon

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Figure 4.6: Forming technique with negative initial gap

higher than that obtained in the step 3 of the previous one because the rubber pad here is initially compressed.

Figure 4.7: Multipoint Incremental forming

Considering the phenomena complexity, induced by multiple interactions between multi-point tools, interpolators and work- piece. Finite element analysis approach was under-taken, to investigate the new process, analysis are focused in recent works on the most in uent parameters on the quality of the nal product, such as, the step between elements (punch element density of the discrete dies), the radius of curvature of the extremities of punch elements, the thicknesses of the GF’s Godavari College of Engineering, Jalgaon

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blank and the elastomeric interpolator. It emerges essentially, that an increase of the punch elements density, the thicknesses of the initial blank and the interpolator, improve the nal part quality, with better thicknesses distribution, reduced residual stresses and dimples. Development of innovative sheet metal forming technologies in last years determines progress in control systems and construction of presses and tools. Considerable growth of forming techniques may be noticed in hydroforming, electromagnetic metal forming, sheet metal forming with elastic tools, cavity forming processes (pneumatic bulging) of superplastic sheet metal forming, laser forming and laser assisted forming, magnetic-pulse forming, shot peen forming and methods of incremental forming. Multi-stage SHF increases the formability of structural parts SHF technologies are now commonly used in automotive industries to produce fuel tanks and tubular parts for exhaust systems. The last technological development in hydroforming techniques consists of combining tube bending, tube hydroforming and tube welding in a exible manner using recon gurable machine tool equipments easily adaptable to various production batches Flexforming is a type of hydroforming process in which the sheet metal is forced to take the shape of a rigid die by the action of uid pressure which acts through a rubber diaphragm (Fig. 8). In this process there is only a single rigid die providing low die costs, the easy modi cation of the dies after changes leading to fast tryouts, and nally high quality parts. The exforming process needs special presses to stand for high pressures up to 80 MPa in the pressure chamber. Sheet metal forming with elastic tools is commonly used in aircraft industry, especially for forming stainless steels nickel alloys sheets.

Figure 4.8: The schematic Representation Of Flexoforming

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4.3

Microscale Laser Forming

In the microscale laser exible forming process, ultrahigh strain rate deformation is generated, due to the ultrahigh pressure and ultra short impacting time of this process . The appliance of microscale laser exible forming is shown in Figure 9. It is composed of laser beam, blank holder, con nement layer, soft punch, specimen, micro mold, lift platform and mobile platform.

Figure 4.9: microscale Laser Forming

The forming principle of microscale laser exible forming is presented as follows. Through the transparent con nement layer, a laser beam irradiates on the soft punch. Then the black substance on the surface of the soft punch absorbs the laser energy and plenty of plasma with high pressure is produced. The con nement layer prevents the plasma expanding upward, so the plasma moves down and a large shock wave is induced. Impacted by the induced shock wave, the soft punch is squeezed into the micro mold, and the specimen is deformed to a certain shape. Therefore, the heat model of the laser, is not involved in microscale laser exible forming.

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Chapter 5 Advantages of Flexible Forming Over Convectional Forming 1. In this process used very exible materials like rubber based , will be less likely to damaged sheet metal parts. 2. Highly complex part can be drawn or shaped easily with less removal of ma-terial. 3. Greater labour Productivity. 4. Flexibility in design obtained. 5. Low capital cost of equipments. 6. Low application of forces required on punches. 7. Operation time required as compared to conventional forming. 8. Production rate will be increases of components . 9. High surface nish are obtained. 10. Wear rate of die are low as well as quality of product improved.

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Chapter 6 Disadvantages of Flexible Forming Over Convectional Forming 1. It is limited to sheet metal forming. 2. Non-conducting materials cannot be produced without the aid of conducting materials. 3. Inferior creep resistance. 4. High cost of uids and material required. 5. Wire form cannot be produced.

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Chapter 7 Applicatons 1. It is most of used in an aircraft bodies and skins. 2. An automobiles bodies and doors. 3. Windows and door frames , oor structured etc. 4. Propulsions and ducting systems. 5. Domestic utensils and cans. 6. It is most likely used in curved shape products like cup forming.

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Chapter 8 Future Scope As a new exible-die forming method, there is still much work to do in the fu-ture. The multipoint exible hydroforming is an adequate mixing of the bene ts of multipoint exible forming and hydroforming processes; the result is an improved resourceful process with upgraded quality and reduced number of component. The future research are focused on the geometrical dimensions and forming limits of components . The numerical model will be also developed by the introduction of appropriate damage law I order to predict the failure of part. It will be widely used in the ship building and airplane manufacture industries This version allows accurate, precise and low cost technology with great saving in time manufacturing especially in the eld of fast prototyping, small batch or single production. Concerning the material research and development, the increasing application of high-strength steels as well as the so-called multi-material concept was emphasized.

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Chapter 9 Conclusions In this study, recent development trends in sheet metal forming were overviewed concerning the applied materials, the forming processes, as well as the tooling concepts and die design practice. Among the many new, innovative process developments, some selected examples were shown including the application of single point and multipoint exible forming, laser technology and hydroforming processes. On this system multi-point die forming, multi-point press forming, multi-point half press forming and multi-point step forming can be automatically realized on line . The cost of the exible manufacture of sheet metal forming is reduced, and the cycle of die design and manufacture is shortened. This action cannot be achieved by the conventional deep drawing technology unless multi stage micro deep drawing is adopted which necessitates di erent forming punch and die sets. As a result, this proposed technique will make the production of micro metallic cups of signi cantly lower overall cost and high quality Flexible multipoint hydroforming using metallic sheet medium is an innovative version of multipoint exible hydro-forming, using of one metallic sheet media instead of con thventional die and punch technique at as follows an improvement of quality of formed thin shell products compared to methods using elastomeric media for the same punch density.

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References [1] Huixia Liu 1, Wenhao Zhang 1, Jenn-Terng Gau 2, Zongbao Shen 1, Youjuan Ma 1, Guoce Zhang 1 and Xiao Wang 1 Department of Mechanical Engineering, Northern Illinois University, DeKalb, IL 60115, USA; jgauniu.eduReceived 14 June 2017; Accepted: 15 July 2017 Published: 18 July 2017 Harbin150001, Chinaa. [2] Liu, H.X.; Sun, X.Q.; Shen, Z.B.; Li, C.; Sha, C.F.; Li, L.Y.; Gao, S.; Ma, Y.J.; Wang, X. The size e ect of deformation behavior in microscale laser shock exible drawing. Opt. Laser Technol. 2016, 86, 93102. [3] uid Zhong-jin Wang, Pengyi Wang, Hui Song National Key Laboratory for Precision Heat Processing of Metals, School of Materials Science and Engineer-ing, Harbin Institute of Technology, (2014) [4] Mao, T., and Altan, T., Aluminum Sheet Forming for Automotive Applications, Part I Material Properties and Design Guidelines, Stamping Journal, Jan Feb. 2013, p. 12 [5] Irthiea, I., Green, G, Hashim, S., and Kriama, A. (2014) Experimental investigation on micro deep drawing process of stainless steel 304 foilusing exible tools. International Journal of Machine Tools and Manufacture, 76 . pp. 21 33. ISSN 0890-6955 (2013) Elsevier Ltd. [6] Karbasian, H. and A.E. Tekkaya, 2010: A review on hot stamping, Journal of Materials Processing Technology 210, 2103-2118.

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[7] Tisa M (2013) Recent development trends in sheet metal forming, Int. J. Microstructure and Materials Properties, Vol. 8, Nos. 1/2, pp.125140.

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