Metal Forming (Engineering)

Post-print of "SM Mirfalah-Nasiri, A Basti, R Hashemi (2016) Forming limit curves analysis of aluminum alloy considering the through-thickness normal stress, anisotropic yield functions and strain rate, Abstract Based on three anisotropic yield criterions including Karafillis-Boyce (K-B), Yld96 and Yld2011, directional normalized uniaxial yield stresses, directional r-value and forming limit curve (FLC) for AA3104-H19 aluminum alloy under plane stress condition are numerically investigated in this article. Moreover, considering through-thickness normal stress effect the forming limit diagram (FLD), stress-based forming limit diagram (FLSD) and extended forming limit stress diagram (XFLSD) is also studied theoretically based on Yld2011 yield criterion and modified Marciniak-Kuczynski (M-K) model. The nonlinear equations set are solved employing Newton-Raphson numerical method to calculate limiting strains. The anisotropic plastic behavior and FLC of AA3104-H19 predicted by Yld2011 yield criterion is in good agreement with experimental data and is more accurate than those of K-B and Yld96 yield functions. In addition, according to FLD, the formability of sheet metal increases by applying the through-thickness normal stress. The effects of strain rate at quasi-static condition and temperature are theoretically investigated on the FLD of AA3104 sheets. The positive temperature sensitivity and negative strain rate sensitivity are observed of FLD of AA3104 alloy.

In the current paper, numerical results of cylindrical cup drawing of aluminum-lithium sheets using the commercial software abaqus/explicit are presented. This software permits investigating physical models of real procedures putting singular emphasis on geometrical non-linearities produced by large deformations, material properties and complex conditions. Numerical simulation using finite element methods (fem) offers the ability of analysing the feasibility of a process, allowing the benefit of saving time and reducing costs by comparison with traditional methods. The 2090 t3 aluminum-lithium alloy was studied with the focus on the influencing plastic anisotropy that affect the final predicted part. The results illustrate that anisotropy influence the thickness variation, and a comparison between anisotropic and isotropic yield was discussed.

Multi-axial incremental forging and shearing (MAIFS), as a new severe plastic deformation technique, was successfully applied up to eight passes on the workpieces of commercially pure Al (AA1100). The microstructure evolutions and mechanisms of the grain refinement in the billets deformed through various passes of process were studied using the electron backscatter diffraction (EBSD) analysis. Microhardness measurements and tensile tests were carried out to evaluate the mechanical properties and deformation behavior of the material after successive passes of the MAIFS process. Measured microhardness evolution indicated that while the distribution of hardness was non-uniform after odd-numbered passes up to four passes, but thereafter outstanding deformation homogeneity was achieved when the consecutive MAIFS passes were applied. Tensile tests indicated that yield stress and ultimate tensile strength increased rapidly during the primary pass of process but thereafter there was only a minor increase up to four passes. After that, a little drop could be observed in strength and then it reached to a saturated magnitude. Measured microhardness distribution values exhibited the same trend, viz. it increased through successive passes to a limiting value beyond which it showed a minor decline by disappearance of points having maximum hardness. Some coarsening was taken place and the dislocation walls between the boundaries were reduced significantly in going from four to six passes. It was suggested that the absorption of the dislocations into grain boundaries as an effective recovery process under large deformations and short-range migration of grain boundaries might be significant mechanisms responsible for the softening observed after four passes of process.

Packaging is every product, regardless of the nature of the material from which it is made, that is intended for containing, storage, protection, handling, delivery and presentation of goods, from raw materials to finished products, on the way from manufacturer to the user or consumer (SN FBiH 33/03 and 72/09, regulation on the management of packaging and packaging waste, the Federal Ministry of Environment and Tourism).

Metals as packaging materials have a number of good properties: impermeable for liquids, gases, microorganisms and electromagnetic rays. They have a high mechanical strength and so they can be used for production of packaging which requires high mechanical strains. Metals are very good conductors of heat and can withstand heat, so metal packaging is suitable for products which are thermally sterilized.

Under the metal packaging materials we can find: black plate, tinplate, chromium coated plate, aluminum plate and aluminum rondels. For making black, white and chrome-plated plate we can use thin low carbon steel strips obtained by cold rolling, and for the production of aluminum plate we can use cold-rolled thin aluminum strips, while the aluminum rondels is obtained by molding or by cutting from hot rolled thick aluminum strip.

Metal packaging has a very wide range of applications. It is used for packaging food, beverages and many other products. Finished metal packaging is delivered to users in the form of: cans, buckets, barrels, lids for jars, shutters bottles, tubes, aerosol (spray) dose, metal boxes, tanks and containers.

Tarihi eserlerde demir metalinin kullanımı genel hatlarıyla strüktür elemanı, kaplama
malzemesi, doğrama elemanı, dekoratif (süsleme) ve yardımcı malzeme olmak üzere
çeşitli gruplar altında kategorize edilebilir. Bu incelemede, tarihi süreç içerisinde demir
malzemenin geleneksel mimarideki genel uygulama yer ve biçimleri ele alınarak, üretim
teknikleri ve şekil verme yöntemleri açıklanmakta, aynı zamanda demir malzemede
zaman içerisinde ortaya çıkan çeşitli problemler ortaya konulmaktadır.

Welding is a widely used process in industry because welding techniques have some striking features which are included in this project. In other way of saying, welding techniques will be so important in human life in the future because of their unique specialties. For this reason, researches and studies on welding are increasing day by day.
Welding is used in different areas in industry and it has various features. Welding is especially used in the manifacturing area, as a connector between materials in the existence of heat and pressure (with or without additional materials). The main targets in this process are; lowest cost, highest satisfaction in performance and longest life.
In this project, the importance of choosing a suitable production regarding to the intended features and how to improve the mechanical features, tried to be explained. Therefore, the welding process which is going to be applied to the materials which has different metal content, are virtually modelled by using Ansys Workbench software.
Parameters as, used materials and chosen welding techniques within this project are widely explained.  Experimental studies were done in order to help the project to enlighten the future studies and to make the project based on numerical data (simplifies prooving). In the other parts of the experimental studies, welding process is applied to the materials which have different metal contents by using Ansys Workbench software. Modelling a material using different welding techniques before production gives  more practical and more proactive vision.

"Generally, in steel processing systems, steels are heated via induction or combustion furnaces. Natural gas fired furnaces have installation costs advantage
while the induction furnaces have the advantages of less scale formation on the surface of the workpiece as well as less environmental pollutions. The
operation cost of both systems is a vital argument to be solved. In this paper, a natural gas fired and induction heating furnaces of a forging process were
studied. Thermodynamic analysis was performed for the furnaces which heat the steel workpiece up to 1,300 °C. The energy performances of both
systems were analyzed and compared. It is concluded that, instead of a natural gas fired or an induction furnace, a hybrid furnace may save more energy
and cost."

It is well known that soft iron owes its transformation into steel to the addition of carbon. Carbon is the hardest substance on Earth - diamond. Carbon is the mainstay of Life on Earth, since everything living on our planet is built from it. This all means: carbon is the mainstay of our world. But find out: it is also the stronghold of the entire Universe! The mythical metal orichalcum spoken of by Plato and Tolkien's mithril are carbon, structurally superior to diamond. The Moon is made from it by the hand of God. The UFO is made from it by the hand of the Other. // Общеизвестно, что своим превращением в сталь мягкое железо обязано добавке углерода. Углеродом есть самое твердое вещество Земли — алмаз. Углерод — оплот Жизни на Земле, ибо из него на ней построено живое. Все это означает: углерод в нашем мире есть главная твердь. Но узнайте: он есть и твердь Мира! Мифичный металл орихалк, о каком рек Платон, и мифрил Толкина — это углерод, структурно высший над алмазом. Из него рукою Бога сделана Луна. Из него рукой Иного сделан НЛО.

An analysis of the etymology of the unknown word "ziff" in the Book of Mormon and an analysis of the usage in a Mesoamerican context.  Also included is a metallurgical analysis of the Book of Mormon plates as to dimensions and alloy content.

This paper presents a modeling approach implemented to consider the effects of the process parameters of Abrasive Jet Machining (AJM), namely applied pressure (Pr), standoff distance (SoD), nozzle diameter (dn) and particle grain size (dg) on machining performance. In particular, a previously reported model of the AJM was adapted to improve its capability to predict material removal rate (MRR) more accurately. In order to validate the developed model experimentally and at the same time to examine the influence of the machining conditions on the MRR, a series of drilling tests have been carried out on glass workpieces using sand as an abrasive powder. After each cutting trial, the MRR was quantified which enabled characterizing the influence of the applied process parameters on the machining performance in terms of resultant MRR. In addition, the experimental results were compared with those obtained by the proposed model, where a relatively acceptable agreement between both results was achieved with an average error of 39%. Also, the experimental results have revealed that MRR is highly dependent on the kinetic energy of the abrasive particles and the applied pressure was found to be the most significant parameter that dominated the material removal rate.

The authors propose a model for the study of a hot rolling process, and the approach is based on thermo-mechanical analysis using the Finite-Element Method (FEM). The model can be used to speed up and improve the design and evaluation of the roughing and finishing phases in plate and sheet production. It is able to calculate the temperature distribution in the roll and the plate, the stress and strain fields, throughout a transient analysis done starting from the first phases of the process. The main hypotheses adopted in the formulation are: the elasto-plastic behaviour of the material; and rolling under plane-deformation conditions. The main variables that characterise the rolling process, such as the geometry of the plate and the roll, the loads and the boundary conditions (radius of the rolls, rolling speed, initial and final thickness, initial temperatures of the plate and the roll), have been expressed in a parametric form, this approach giving a good flexibility to the model. During the simulation, an iterative procedure enables the calculation and updating of the load conditions, such as the heat produced by friction on the plate–roll contact arc, and that caused by plastic deformation. The congruence of the results has been evaluated using experimental and theoretical data available in the literature.

Alteration of forming and failure limits due to planar anisotropy of the sheet metal significantly affects the safe forming operation region and finally successfully manufacturing of a sheet metal formed component. This article presents the effect of planar anisotropy on uniaxial tensile properties, forming and failure limits of cold-rolled ferritic and dual-phase steels. In-situ three dimensional digital image correlation technique is used to measure the evolution of local strain components during uniaxial tensile test. For both the steels, necking limit is highest for the specimen at an orientation of 90°t o rolling direction, while failure limit is highest for those specimen whose orientation is 45°to rolling direction for ferri-tic steel, and both 0°and 90°to rolling direction for dual-phase steel. Uniaxial tensile deformation path for ferritic steel holds lower slope than dual-phase steel as depicted in major versus minor strain plot.

We discuss methods to map crystallographic textures in crystal plasticity finite element simulations. Fourier-type series expansion methods which use spherical harmonic library functions as well as the direct pole figure inversion methods are not well suited to reproduce texture information in a sufficiently localized spherical form onto finite element grids. Mathematically compact Gauss-shaped spherical texture components represent a better approach for including textures in finite element models since they represent an excellent compromise between discreteness (spherical localization), compactness (simple functions), mathematical precision (very good approximation also of complex orientation distribution functions already with small sets of texture components), scalability (the number of used texture components can be systematically varied according to the desired exactness of the texture fit), conceptual simplicity (simple mathematical handling), and physical significance (texture components can be directly linked to characteristic metallurgical mechanisms). The use of texture component functions has also advantages over the use of large sets of discrete single orientations with equal scatter and height since they are more compact, practical, and provide better physical insight into microstructural mechanisms and composition sensitive effects. The article presents a new approach for the mathematical reproduction of such crystallographic texture components in crystal plasticity finite element simulations. It explains in some detail why they are particularly suited for this purpose and how they can be used to map and recover textures in/from plasticity simulations.

In this study, the microstructural variations, mechanical properties and forming limit diagrams (FLD) of Al 2024 aluminum alloy sheet with the thickness of 0.81mm are investigated during natural ageing (T4) treatment. The most formability in Al 2024 can be achieved just after solution treatment, and it is better to perform the forming process,
on this aluminum alloy sheet, in this condition. However, in industrial applications, there is usually a postponement for some hours after solution treatment to begin the forming process that it means the forming process should be done at the natural ageing condition. This condition decreases the formability of Al 2024 sheets. To monitor the properties variations in natural ageing condition, FLDs were determined after specific times (e.g., 0.5, 1.5, 4 and 24 hours). The variations in micro-hardness, yield strength, ultimate tensile strength and elongation at break were observed with changing the ageing time. The scanning electron microscope (SEM) investigations illustrated that density and size of precipitates were changed with ageing time. Moreover, the Nakazima test was utilized to study the forming limits con -sidering the natural ageing condition. Results showed by increasing the ageing time, up to 4h, the majority of properties variations could be seen, and from 4h to 24h, the variations were changed slower.

The rectangular cross-section copper profiles are widely used in various industries. These tubes and profiles are formed in a small radius to decrease the weight and occupied space. The smaller bending radius, the higher the probability of defects, especially when the cross-sectional area of the tube is non-circular. Because by decreasing the bending radius, it is possible to create fold defects in the inner radius of the bend, excessive thinning of the outer wall, and changing the cross-sectional shape. In these situations, conventional tube bending techniques cannot produce these bends with optimal quality. Therefore, it is necessary to provide innovative, and new methods for the production of small radius bends in non-circular tubes. One of the most reliable and suitable bending methods for tubes and the profiles are flexible bending. In this study, a flexible bending machine has been fabricated based on a novel approach. Also, the key parameters in flexible bending of rectangular copper profiles such as: feeding speed, clearance between the die and profile, offset (u), guide fillet radius, the distance between the fixed die and movable die (v) and friction with ABAQUS finite element method software have been investigated. The numerical results have been compared with experiments. Experimental results showed good compatibility with simulation results.

A novel severe plastic deformation (SPD) technique entitled Multi-Axial Incremental Forging and Shearing (MAIFS) has been introduced and the preliminary evaluation of this technique by characterizing the material flow has been described in this paper. The MAIFS process is the combination of incremental forging (or incremental back extrusion) followed by angular pressing. The streamline visualized data of a tin-based alloy as the representative of the soft deformable metals was utilized to predict the strain distribution experienced by material during deformation induced by MAIFS process. It was demonstrated that acceptable deformation homogeneity can be achieved after pass two of the process, and the workpieces were deformed up to four passes of MAIFS without any crack or discontinuity. The first results of numerical simulations of proposed process after four consecutive passes proved its general feasibility, and comparison of acquired data with the simulation results of same specimen processed by four passes ECAP through route Bc confirmed the capability of MAIFS process. An attempt has also been made to primarily investigate the potential of the process for grain refinement.

An enhanced unfolding inverse finite element method (IFEM) is used together with an extended strain-based forming limit diagram (EFLD) to develop a fast and reliable approach to predict the feasibility of the deep drawing process of a part and determining where the failure or defects can occur. In the developed unfolding IFEM, the meshed part properly folds out on the flat sheet and treated as a 2D problem to reduce the computation time. The large deformation relations, nonlinear material behavior and friction conditions in the blank holder zone are also considered to improve the accuracy and capability of the proposed IFEM. The extended strain-based forming limit diagram based on the Marciniak and Kuczynski (M-K) model is computed and used to predict the onset of necking during sheet processing. The EFLD is built based on equivalent plastic strains and material flow direction at the end of forming. This new forming limit diagram is much less strain path dependent than the conventional forming limit diagram. Furthermore, the use and interpretation of this new diagram are easier than the stress-based forming limit diagram. Finally, two applied examples are presented to demonstrate the capability of the proposed approach.

Wrinkling, which is primarily caused by insufficient blank holder force, is a significant issue that induces inconsistencies in forming parts, particularly in the deep drawing process. In this article, an investigation of the wrinkling in the deep drawing process of two-layer sheets is performed through an analytical approach, numerical method, and experimental tests. Increasing in the blank holder force, the process is under control by the proposed algorithm. Consequently, it aims to find the minimum required blank holder force to avoid wrinkling. The energy technique is utilized to predict the wrinkling in the analytical approach. Similarly, finite element simulations are implemented to investigate the effect of forming parameters on wrinkling. The experimental tests are performed to verify the analytical and numerical results. The impact of the material properties and stacking sequences (lay-up) on blank holder force and forming force are studied. Results show that the optimum blank holder force is dependent on the material properties, blank geometry, and layer stacking sequences. Also, a good agreement between analytical, numerical, and experimental results is achieved.

The article discusses an innovative method of reducing the loss of gold with waste cyanide solutions. To conduct this study, chemical reagents were used that allow the removal of harmful impurities and create the optimal conditions for the complete leaching of gold-bearing ores. The results show that the introduction of this technology in industry will increase their productivity.

A construção da Ponte Marechal Hermes sobre o rio São Francisco estava inserida no ambicioso projeto de expansão da Ferrovia Central do Brasil que pretendia interligar a então capital do Brasil, Rio de Janeiro, a Belém do Pará, no norte do País. A integração do litoral com o interior do Brasil sempre foi vontade das administrações luso-brasileiras e foi planejada, de diferentes formas, em outros momentos da história.

When I think about metal, I have in mind some
features like Malleability (the ability to be hammered
or pressed without breaking or craking),
fusibility (the ability to be fused or melted) and
ductibility (the ability to be drawn out into wires).
These are manipulability1 features, they give us
the idea what we can do with the material in
terms of transformations. On the other hand we
can see metals through the physical phenomena
such as electrical and thermal conductivity or in
some cases magnetism. We could even go deeper
in the understanding of the material within
the chemical/physical dimension, with implication
in nanotechnology and the idea of programmable
matter2.
These considerations give me the possibility to
distinguish different ways of transformation of
the material, let consider them in two families:
the first one where the hand and the machinery
as an extension of the hand, are the control
tools, the drivers. The second one, where the drivers
are the interactions of physical conditions.

To better investigate the realm of the material,
we have to use our body. We think physically, so
the point is to expand it directly to give us the
possibility to see things differently, from an augmented
perspective. Our body is able to easily
incorporate exogenous apparatuses, able to let
us think process, and to do so we have to reinforce
the idea of a “totalizing immersion”, a bodily
experience able to activate our senses, but not
only, able to refine them, able to expand them to
new realms. To build new senses and new sensitivities,
to bring back intelligence and sensitivity in
our manufacturing processes and to bring back
intelligence into the material itself.

Tube compression forming is defined as the ability of a metal to deform plastically or change the shape of the tube into a new desirable shape without failure. To control the operation of tube compression forming without failure, a FLD (formability limit diagram) is invariably used to determine the acceptable range of critical deformation. Every tube has its own limit of ductility, which determines its formability and strain state. FLD can be evaluated by using theoretical, experimental and simulation approaches. In this paper, the experimental evaluation of the forming limit for an aluminum alloy tube in electromagnetic forming under various energy levels, and roll forming under different pressures, are discussed. This method allows the determination of the forming-limit, and the strain and stress diagrams. Further this study makes an analysis of the influence of the material behaviour parameters under various energy and pressure levels. It is found that the electromagnetic compression forming processed aluminum alloy tubes have good formability behaviour compared with roll compression forming.

The deformation and strain measurements have always been one of the main issues in structural engineering. Measuring displacements accurately without damaging structures are an important aim in experimental analysis. For an example, the existing structures need to be evaluated whether they are still fit for purposes or not. To assess complex structures, we need an acceptable and enough amount of data Current strain measurement technologies are not capable of evaluating compounded structures. This paper investigates on an alternative method that uses digital images to provide a full displacement and strain field called Digital Image Correlation (DIC); This technique compares the digital images taken from digital cameras, before and after deformation. We also calculated the coefficient of plastic anisotropy. An aluminium 1050 specimen was loaded in tension according to ASTM E8 testing method while the Sony camcorder captured the video of the specimen being loaded. Once the video was captured, the images were snapshot from video strip using a built-in function of the camera. After that, the images were processed using the Matlab software. The results determined by the extensometer and the optical strain measurement method were compared to each other. This comparison shows that if the test's setup could be configured in a good way, the error will be less than 2%.

ABSTRACT Generally, in steel processing systems, steels are heated via induction or combustion furnaces. Natural gas fired furnaces have installation costs advantage and induction furnaces have the advantages of less scale formation on the surface of the workpiece as well as environmental reasons. The operation cost of both systems is a vital argument to be solved. In this paper, a natural gas fired and an induction-heating furnaces of a forging process were studied. Thermodynamic analysis was performed for the furnaces which heats the work piece up to 1300 C. The energy performances of both systems were analyzed and compared. For the heating process a hybrid furnace was suggested.

For the first time in this study, the accumulative press bonding (APB) method was used to fabricate layer composites, including ceramic powder and metallic layers, and the spring back as a functional plasticity test experimentally investigated. Al/Cu and Al/Cu/Al2O3 composites were successfully manufactured in five APB cycles, and in addition to spring back evaluation, mechanical properties, and plastic instability were investigated. The results showed that by the end of the third cycle, both composites were fully layered structure. However, in the fifth cycle in the Al/Cu/Al2O3 composite, plastic instability intensified and necking and fracture at all Cu layers observed due to the presence of particles in the interface and further differences in mechanical properties. As the number of APB cycles increases, the number of Al/Cu interfaces, which are the place where the reinforcement particles are dispersed, increases, thereby significantly improving the particle distribution and mechanical properties. The mechanical properties were improved by increasing the applied strain to the two composites, mainly due to the mechanisms underlying the severe plastic deformation (SPD) processes, including cold working and microstructure improvement. The mechanical properties of the composite containing reinforcing particles improved the tensile strength and microhardness of both layers in all APB cycles, although the amount of elongation decreased slightly. The maximum tensile strength values of the two composites were obtained at the end of the fifth cycle, which improved the tensile strength for Al/Cu and Al/Cu/Al2O3 by about 2.65 and 2.42 times higher than unprocessed Al matrix, respectively. Experimental results of the spring back evaluation showed that the composite with reinforcement powder due to the higher Young's modulus had lower spring back value. The amount of spring back in both composites decreased with almost the same rate as the applied strain increased.

The direct thermal method is used for the creation of globular microstructures suitable for semi-solid metal forming. In this paper, both simulation and experimental results using direct thermal method are presented. ProCAST® software was used to estimate temperature distribution inside the aluminum billet. In validation work, molten aluminum A356 was poured into metallic copper tube molds and cooled down to the semi-solid temperature before being quenched in water at room temperature. The effect of pouring temperatures of 630°C, 650°C, 665°C, 680°C and holding times of 45 s and 60 s on the microstructure of aluminum A356 alloy were investigated. The simulation results showed that the average temperature rate within the copper mold, from initial pouring temperature to just before quenching, was approximately 1°C/s. Examination of the solidified microstructures showed that the microstructure was more spherical when lower pouring temperatures and holding periods were used. From the micrographs it was found that the most globular and smallest structures were achieved at processing parameters of 630°C and 45 s.