Search

This study presents the development of a material selection decision support system for an automotive rooftop tent. The system uses five parameters of material cost, formability, corrosion resistance, tensile strength and hardness to optimize material choice from a list of aluminium alloy options. This was done before production via the deep drawing process can commence. The parameters were quantified using the average market prices for each alloy, product requirements obtained from the case study and the performance data that was obtained from the uniaxial tensile and hardness tests. These inputs were combined with the developed material selection framework and then programmed into a web-based decision support system for automated, data-driven material selection. The output presents the recommendation for the optimum material that balances cost-effectiveness and performance. The decision support system was successfully used to select the optimum alloy for the rooftop tent. Results show that AA1050 is the optimum material, providing weight reduction at the minimum achievable cost without compromising the product requirements for the rooftop tent. The decision support system is also scalable, and this allows it to be used with larger datasets for different products and processes in the future. [ABSTRACT FROM AUTHOR]

Deep drawing is the process of drawing sheet metal blank into a desired shape. A blank holder is used to prevent wrinkling in the product, especially with thin sheets. The implementation of this process requires the use of double action press, and when the blank-holder is eliminated, single action press can be used, thus saving energy. In the current study, a new arrangement of punch and die was adopted to produce a square cup of brass from thin sheet in a single stroke of reverse deep drawing without blank-holder. Square cup produced by pushing blank with a hollow square punch through a square outer die which has inner square die. The geometric shape of the blank and its dimensions can affect the determination of the wrinkling as well as the drawing load and the distribution of strain and thickness, in addition reducing the metal removed as a waste in the trimming process of product. To study the effect of this parameter numerically and experimentally, three shapes were employed, square, square with fillet at its corners, and circular blank. The results show that the square blank gave a successful square cup of 30 mm rib, and 20 mm height has 4 mm radius without wrinkling. The maximum load and thickness distribution were almost similar for all blanks and an apparent change appeared in the thickness of the base. The maximum strain value decreases in the square blank. The speed of the punch can affect the determination of the drawing load, so three punch speeds (3, 6 and 9 mm/min) were experimentally employed to investigate their effect on load. The results revealed that the speed of 6 mm/min was the best. Errors between numerical and experimental results don't exceed 10%. [ABSTRACT FROM AUTHOR]

In parallel with the development of production technologies and considering limited energy resources within the scope of sustainability, the demand for parts with complex geometry and high strength that can be produced with low energy consumption, with the lowest amount of raw materials and wastage, is increasing. One of the most important processes by which these types of parts can be produced is the sheet metal forming method. The deep drawing process, in which both the part and the tool are exposed to extreme loads, is widely used in the production of high-strength parts with tight tolerances. It is expected to have high tribological performance against friction and wear occurring in deep drawing tools due to overloads. The process of creating texture on tool surfaces is one of the methods that has attracted attention recently and increases tribological performance. In this study, surface texture was created on the tool surface using industrial shot peening processes. Dry and liquid friction test results on uncoated and CrN coated textured surfaces were compared with flat surface test results. The kinetic friction coefficient decreased from 0.21 to 0.16 (25%) and from 0.15 to 0.06 (60%) in the case of dry and liquid friction, respectively. In CrN coated tribology tests, while there was no decrease in dry friction, the kinetic friction coefficient decreased from 0.09 to 0.05 (41%) in liquid friction. [ABSTRACT FROM AUTHOR]

Highlights Carbon Fiber Reinforced Polymers (CFRP) is one of the ideal materials in the field of automotive lightweight. As one of the traditional manufacturing processes of CFRP, autoclave process has long production time, high cost and complicated operation. To overcome these shortcomings, deep drawing can be used for CFRP forming. It has the advantages of stable product quality, good repeatability, low cost, simple operation and can produce parts with complex shapes. In this paper, the influence of lay‐up sequences on the drawability of cylindrical parts was studied by using self‐made deep drawing device. The results showed that among the four lay‐up sequences [0]°12, [0/90]°6, [0/90/45/‐45/90/0]°S and [15/30/……/180]°, the [15/30/……/180]° lay‐up parts had excellent deformation coordination ability due to less angular variation in the fiber direction, and the maximum depth of 21.99 mm could be obtained. Due to the influence of wrinkles, the thickness of [15/30/……/180]° parts increased at the die corner and side wall. The thickness decreased at the flange, punch corner and bottom due to the compressive pressure. In addition, [15/30/……/180]° lay‐up parts benefited from the high level of in‐plane isotropy of the helicoidal structure, it had the fewest forming defects. The resin poor areas and resin rich areas were less and no fiber cracks were found. Investigated the influence of lay‐up sequences on the drawability of CFRP. The forming depth of [15/30/……/180]° parts was 21.99 mm. [15/30/……/180]° lay‐up parts had the best drawability. No cracks were found on the [15/30/……/180]° part. [ABSTRACT FROM AUTHOR]

Deep drawing has been practiced in various manufacturing industries for many years. With the aid of stamping equipment, materials are sheared to different shapes and dimensions for users. Meanwhile, through artificial intelligence (AI) training, machines can make decisions or perform various functions. The aim of this study is to discuss the geometric and process parameters for A7075 in deep drawing and derive the formable regions of sound products for different forming parameters. Four parameters—forming temperature, punch speed, blank diameter and thickness—are used to investigate their effects on the forming results. Through finite element simulation, a database is established and used for machine learning (ML) training and validation to derive an AI prediction model. Importing the forming parameters into this prediction model can obtain the forming results rapidly. To validate the formable regions of sound products, several experiments are conducted and the results are compared with the prediction results to verify the feasibility of applying ML to deep drawing processes of aluminum alloy A7075 and the reliability of the AI prediction model. [ABSTRACT FROM AUTHOR]

The aim of this article is to provide an analysis of the influence of the type of hard anti-wear coatings on the friction behaviour of DC01 deep-drawing steel sheets. DC01 steel sheets exhibit high formability, and they are widely used in sheet metal forming operations. The tribological properties of the tool surface, especially the coating used, determine the friction conditions in sheet metal forming. In order to carry out the research, this study developed and manufactured a special bending-under-tension (BUT) friction tribometer that models the friction phenomenon on the rounded edges of tools in the deep-drawing process. The rationale for building the tribotester was that there are no commercial tribotesters available that can be used to model the phenomenon of friction on the rounded edges of tools in sheet forming processes. The influence of the type of coating and sheet deformation on the coefficient of friction (CoF) and the change in the topography of the sheet surface were analysed. Countersamples with surfaces prepared using titanium + nitrogen ion implantation, nitrogen ion implantation and electron beam remelting were tested. The tests were carried out in conditions of dry friction and lubrication with oils with different kinematic viscosities. Under dry friction conditions, a clear increase in the CoF value, with the elongation of the samples for all analysed types of countersamples, was observed. Under lubricated conditions, the uncoated countersample showed the most favourable friction conditions. Furthermore, oil with a lower viscosity provided more favourable conditions for reducing the coefficient of friction. Within the entire range of sample elongation, the most favourable conditions for reducing the CoF were provided by uncoated samples and lubrication with S100+ oil. During the friction process, the average roughness decreased as a result of flattening the phenomenon. Under dry friction conditions, the value of the Sa parameter during the BUT test decreased by 20.3–30.2%, depending on the type of countersample. As a result of the friction process, the kurtosis and skewness increased and decreased, respectively, compared to as-received sheet metal. [ABSTRACT FROM AUTHOR]

Through comparing the distribution of blank holder force (BHF) and stress-strain curve along the radial direction, there has been good forming capability and adaptability in deep drawing with the electro-permanent magnetic (EPM) blank holder (EPMBH) technique. However, whether the BHF technique is applicable for non-ferromagnetic materials has yet to be researched. In the paper, taking 08-Al steel and H62 copper plates as examples, the drawability of ferromagnetic and non-ferromagnetic sheets with EPMBH is investigated. Moreover, a series of confirmatory tests were carried out based on numerical analysis. It found that similar to the deep drawing with ferromagnetic slab, there is slight attenuation on the holding effect for non-ferromagnetic sheets, and the effect of gap on the magnetic attraction caused by the magnetic properties of the plate first increases sharply and then slowly decreases, while its possible failure modes are also wrinkling and rupture due to insufficient BHF and excessive drawing height, respectively. In the experiment, flawless deep-drawing workpieces can be obtained with EPMBH, indicating that EPMBH could meet the forming requirement for ferromagnet and non-ferromagnetic plates and can be controllably adjusted through altering the excitation current of the EPMBH device. The experiment result shows that the optimal excitation current is 14 A for ferromagnetic steel plate and 13 A for non-ferromagnetic copper plate with the same diameter of 110 mm and thickness of 0.8 mm. [ABSTRACT FROM AUTHOR]

This work is concerned with forming, specifically deep drawing, and its influence on the micro-mechanical properties of sheet metal. In practice, there are several applications in which fractions can occur due to weak spots in the deep-drawn sheet metal, especially after long-term use. The deep drawing process was carried out on BUP–600 machines using the LHD (Limiting Dome Height) method, which uses a forming tool with a diameter of 100 mm and bead groove. Sheet metals X8CrMnNi19-6-3 (1.4376) with thicknesses of 1, 1.5, and 3 mm were selected for this process. To study the effect of a lubricant on the formability of the sheet metal, deep drawing without and with a lubricant was compared. An FEM analysis was conducted to identify critical points in the deep drawing process, and the results were later compared with real results. The analysis was conducted using the AutoForm program. The micro-mechanical properties of these points were subsequently examined. The specified points on the formed part showed significant differences in their micro-mechanical properties, suggesting a higher strength but also less resistance to fractures. The difference in micro-mechanical properties (indentation and Vickers hardness) in points that were not deep-drawn and points located in critical areas was up to 86%. Significant changes in behavior were found in the indentation modulus and plastic/elastic deformation work as well. This study demonstrates the significant effect of the use of a lubricant in achieving the deep drawing of the sheet metal. The application of a lubricant resulted in a 33% increase in drawing range compared to drawing without lubrication. This study has a significant influence on the deep drawing of sheet metals in practice, showing the fundamental influence of the lubricant on the drawing process and also showing the problem of critical points that need to be eliminated. [ABSTRACT FROM AUTHOR]

The deep drawing process, a pivotal technique in sheet metal forming, frequently encounters challenges such as anisotropy-induced defects. This study comprehensively investigates the influence of various yield criteria on the anisotropic behavior and fracture prediction in SECC steel cylindrical cups. It integrates Hill'48R, Hill'48S, and von Mises yield criteria in conjunction with Swift's hardening law to evaluate material behavior under complex stress states. Experimental and numerical simulations assess the anisotropy effects across multiple orientations (0°, 45°, and 90°), revealing intricate relationships between stress criteria and material response. The findings indicate significant discrepancies between isotropic and anisotropic models in predicting fracture heights, emphasizing the importance of selecting appropriate yield criteria. Notably, the von Mises criterion results in lower fracture heights, suggesting higher susceptibility to fractures, while the Hill'48R model aligns closely with experimental data, validated through variations in punch corner radius and blank holder force parameters, with a maximum deviation of 3.23%. Hill'48S displays moderate plastic deformation characteristics. [ABSTRACT FROM AUTHOR]

In this paper, a new segmental blank holder technique was developed. The blank holder force (BHF) was applied on sheet metal independently and effectively by the binder which was divided into double rings. The principle of holding was derivatized by theoretical formulas, thereby proving that the BHF distribution applied by the new binder is more reasonable. Furthermore, combined with numerical simulation, it can be found that the wrinkling was better suppressed. Finally, the effectiveness of the segmental blank holder technique was proven by a series of experiments with AA5754 plate. It is verified that the flange wrinkling was demonstrated to be more eliminated than that using the single blank holder. Compared with 1:2 and 2:1, when the distribution ratio between the outer ring and the inner ring is 1:2 (the applied BHF is 6.9 kN), there has a better-forming quality. [ABSTRACT FROM AUTHOR]

In directional forming processes, such as rolling and extrusion, the grains can develop preferred crystal orientations. These preferred orientations—the texture—are the main cause for material anisotropy. This anisotropy leads to phenomena such as earing, which occur during further forming processes, e.g., during the deep drawing of sheet metal. Considering anisotropic properties in numerical simulations allows us to investigate the effects of texture-dependent defects in forming processes and the development of possible solutions. Purely phenomenological models for modeling anisotropy work by fitting material parameters or applying measured anisotropy properties to all elements of the part, which remain constant over the duration of the simulation. In contrast, crystal plasticity methods, such as the visco-plastic self-consistent (VPSC) model, provide a deeper insight into the development of the material microstructure. By experimentally measuring the initial texture and using it as an initial condition for the simulations, it is possible to predict the evolution of the microstructure and the resulting effect on the mechanical properties during forming operations. The results of the simulations with the VPSC model show a good agreement with corresponding compression tests and the earing phenomenon, which is typical for cup deep drawing. [ABSTRACT FROM AUTHOR]

The main objective of this study was to analyze the deep drawing behavior of sandwich laminate for various blank shapes and lubrications. Commercially available aluminum sandwich laminate with face sheets made of aluminum alloy, AA2219 and a core made of high-density polyethylene was used for the forming behaviour performance. The laminate was characterized by its mass density, porosity and tensile strength for better understanding the physical and mechanical behavior, being essential for analyzing the forming behaviour. Deep drawing, one of the forming techniques on the laminate was performed with a steel spherical punch for three different blank shapes: circular, square and square with round fillets. Furthermore, three different lubricants Vaseline, grease and soap, were used at the contact regions of the die and laminate. This formation occurred under normal atmospheric conditions. Lubrication significantly influenced the drawing performance in addition to the blank shape. Uniform material flow during the drawing process was achieved in the circular specimen, which in turn resulted in better drawing performance of the laminate. The highest drawing force of 1.425 kN was obtained for the circular specimen with the grease lubricant. A higher-order equivalent plastic strain was observed for the lubricant grease, and the least-order strain was observed for the specimens under dry conditions. The higher the effect of lubrication, the lower the friction between the punch and specimen, which in turn resulted in a higher order strain and subsequent reduction in the thickness of the specimen.

Medical containers that sterilize surgical instruments are constantly needed in the healthcare industry. In line with this need, improvements in the fabrication of medical containers are important. Determining the design factors of medical containers fabricated by deep drawing saves time and cost. This study determined, the design factors of square medical containers and experimentally verified the deep drawing process modeled in Abaqus/Explicit finite element (FE) software. Taguchi statistical method was used to reduce the number of experiments. Blank holder force (BHF), punch radius (RP), die radius (RD), coefficient of friction between die and blank (µDB), coefficient of friction between punch and blank (µPB), coefficient of friction between holder and blank (µHB) as variable factors while selecting thickness reduction (TR) and maximum punch force (PF) were selected as output parameters. The effect of variable factors on the output parameters was determined by ANOVA analysis. As a result of the examinations, it was deter-mined that TR and PF increased as BHF, µDB and µHB values increased, whereas they decreased as RP and RD increased. On the other hand, it was determined that TR decreased and PF increased as µPB increased. In addition, the corners of the sheets were chamfered in different sizes to prevent the formation of ears in the containers. Finally, the appropriate chamfer size was determined by examining the sheet thicknesses. [ABSTRACT FROM AUTHOR]

The research intends to produce conventional and intricate shapes using a deep drawing operation experimental work and finite element analysis (FEA). So, to perform experiment work, the dies of deep drawing were designed, manufactured, and then employed to produce the mugs of cylindrical and polygonal shapes from low-carbon steel (1008-AISI). In addition, a commercial software program, ANSYS (workbench), was applied to perform the numerical analysis. The research aim is to create conventional (cylindrical) and intricate (polygonal has eight edges) shapes in a deep drawing process and compare the experimental work results and the FEA of both shapes. The comparison saw that with the intricate shapes, the maximum drawing force demanded to create a polygonal mug registered at 39.865 and 33.675 kN with the cylindrical mug. The maximum effective strain registered was 0.4542 with mugs of intricate shapes. Conventional shapes (cylindrical) are easier than the production of intricate shapes (polygonal has eight edges) by employing the deep drawing operation. [ABSTRACT FROM AUTHOR]

The study investigates the deep drawing process for bimetallic sheets formed by bonding dissimilar metals (AA1100 aluminium alloy and C36000 brass) with epoxy-based adhesive. Experimental exploration of process parameters, including blank diameter, stacking sequence, lubrication, and strain rate, was conducted to analyse their impact on load–displacement behaviour and thickness strain distribution. Additionally, the study assessed fracture susceptibility, material flow characteristics (tearing and wrinkling), and the requisite drawing force for the bonded specimens. Results indicate enhanced formability and mechanical properties in bonded sheets compared to individual metal sheets, demonstrating the potential advantages of this approach. The bonded sheets demonstrated improved formability and mechanical properties compared to individual metals. Notably, the maximum drawing force for the bonded sheet (170 mm diameter) significantly increased to 24.2 kN, surpassing individual sheets by 69.85% for AA1100 and 40.54% for C36000. The analysis identified a vulnerable region (12–15 mm from the centre) under maximum risk of failure and consistent deformation patterns in samples with varying diameters and lubrication, providing valuable insights into the behaviour of bonded bimetallic sheets in deep drawing. [ABSTRACT FROM AUTHOR]

This investigation delves into the residual stresses that arise during the deep drawing process of laser-welded blanks (LWBs) using a combination of experimental and numerical methods. While LWBs are preferred for their low distortion and high-quality welds, they are subjected to detrimental residual stresses during forming operations that can adversely affect their service life. The primary objective of this study is to evaluate the influence of five essential process parameters, namely welding power, welding speed, blank holder forces (BHF), friction coefficient, and material properties, on the residual stresses that are generated during the welding and forming of LWBs. Moreover, the study seeks to optimize these process parameters for the deep drawing process utilized in this investigation using response surface methodology (RSM). The hole-drilling method, a commonly used experimental technique for measuring residual stresses, was employed in this study to measure the residual stresses in different zones of laser-welded blanks (LWBs). The measurements were performed using a strain gauge rosette and were repeated three times to ensure accuracy. In addition, the Simufact package and Abaqus Unified FEA software are utilized to simulate the laser beam welding and forming processes, respectively. The close alignment between experimental and simulated outcomes suggests that the model is suitable for numerical simulation of the LWB deep drawing process (less than 10%). By conducting an analysis of variance, the main factors that influence the residual stresses in the welding and forming processes are identified. The findings suggest that welding power–welding speed (30.89%) and BHF (21.65%) have the most significant impact on residual stresses. Furthermore, selecting BHF = 50140.67N, friction coefficient = 0.2, welding speed = 7.4 mm/s, and welding power = 144.79W can enhance the confidence coefficient of the welding zone design. [ABSTRACT FROM AUTHOR]

Fiber-metal laminates (FMLs) are rapidly advancing materials that combine the characteristics of resin-based composites and metals. These properties can be further enhanced by incorporating nanoscale particles, resulting in a variant known as FMLs-Nano. This study explores the mechanical properties of FMLs with the incorporation of Graphene Oxide (GO) and investigates for the first time the influence of GO on bonding strength, aiming to improve the laminate's performance during the forming operation by eliminating delamination defects. The goal is to expand the potential applications of FMLs-Nano and enable the production of intricate components. To evaluate the influence of GO, we conducted tests on several mechanical aspects, including tensile strength, flexural performance, and lap shear strength. These tests involved using different GO fractions in the laminate. Microscopy was employed to examine damage patterns and understand failure behavior. Additionally, deep drawing experiments were performed and compared with conventional FMLs to evaluate the GO influence on delamination failure. The results indicate that FML-GO exhibits superior tensile performance compared to conventional FMLs, with FML-GO tensile strength and Young's modulus improved by 11.7% and 13.5%, respectively. Moreover, flexural and interface shear strength showed remarkable improvements, with an increase of 134% and 150% compared to conventional FMLs. These improvements were verified through mechanical testing and further confirmed by scanning electron microscope observations. Additionally, deep drawing experiments demonstrated significant improvement as delamination of the FML layers was successfully eliminated during the forming process. [ABSTRACT FROM AUTHOR]

Copyright of Tikrit Journal of Engineering Sciences is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this research, an innovative method has been applied to obtain the shape of initial sheet in the forming of different rectangular geometries. So that we can define rules that automatically determine the optimal shape of the initial sheet at different heights. Sensitivity analysis method was used for optimization, and Python software was used to link with Abaqus software. By examining the geometrical parameters and forming pressure, a flowchart was presented to determine the appropriate pressure. By examining the height changes in different geometries, it was found that the optimization reduces the maximum pressure and the maximum radius of the punch, which were obtained by 4 and 8%, respectively. It was found that the difference in the size of the longitudinal and transverse sides of the section has a direct effect on the changes in the node coordinates to plot the target curve and reduces the number of optimization steps. According to the results, it was shown that by automation and determining the pressure flowchart, the shape of the initial sheet can be determined without repeating the optimization stages and experimental tests. It also prevents material waste. [ABSTRACT FROM AUTHOR]

Finite element analysis of non-isothermal warm deep drawing of AA5083-O aluminum alloy sheets has been carried out using a coupled thermomechanical numerical model. Two different yield criteria, namely Hill's and Barlat's criteria have been used to define the yielding behavior in the simulations. Using cold punch in combination with hot dies significantly improved the drawability of the sheet material but at the same time resulted in a large thermal gradient and strain rate variation during the process. Therefore, for a better predictive accuracy, the effect of strain rate and temperature has been incorporated into the simulations by defining the stress–strain curves at various temperatures and strain rates. Numerical simulations have also been carried out at different initial blank temperatures and punch speeds to study the influence of temperature and speed on drawability, thinning, and drawing load. The predicted drawability, thinning, and drawing load are found to be in good agreement with the experiments. [ABSTRACT FROM AUTHOR]

The deep drawing process of thick sheet metal for vessel production is carried out by applying a tractrix die with the absence of a blank holder, which has economic benefits for industrial production. The main aim of the paper is the development of a reliable numerical thermo-mechanical model of a silicon brass vessel manufactured by a deep drawing process in a tractrix die and a subsequent ironing process, which includes the previous assembly of the dies with reinforcing rings that creates the required prestresses. The testing of the mechanical properties of silicon brass CuZn24Si was carried out by a standard uniaxial tensile test, thus a flow curve was determined to describe the material behaviour. The initial temperatures of the environment, blank and tools were measured with an infrared thermal imager. A comprehensive finite element stress analysis of the deformable tools was carried out for the assembly phase of the dies, and for workpiece and tools in the deep drawing and ironing processes. The comparison of measured and numerically estimated temperatures had a good agreement, so the developed numerical model was confirmed and validated. This research study demonstrates how different process parameters can be investigated through a reliable and precise numerical model with complementary experimental research for the optimization of industrial technology. [ABSTRACT FROM AUTHOR]

TRIP (Transformation Induced Plasticity) steels belong to the group of advanced high-strength steels. Their main advantage is their excellent strength combined with high ductility, which makes them ideal for deep drawing processes. The forming of TRIP steels in the deep drawing process enables the production of a thin-walled final product with superior mechanical properties. For this reason, this study presents comprehensive research into the deep drawing of cylindrical cups made from TRIP steel. The research focuses on three main aspects of the deep drawing process, namely the sheet metal thinning, the maximum force value and the ear height as a result of the anisotropic material behaviour. Artificial neural networks (ANNs) were built to predict all the mentioned output parameters of the part or the process itself. The ANNs were trained using data obtained from a sufficient number of simulations based on the finite element method (FEM). The ANN models were developed based on variable material properties, including anisotropic parameters, blank holding force, blank diameter, and friction coefficient. A good agreement between simulation, ANN and experimental results is evident. [ABSTRACT FROM AUTHOR]

The paper presents a technique for determining the area of destruction of sheet materials using the combined deep drawing process. Using a linear diagram of the stress-strain state on the workpiece flange, the critical relative thickness was obtained at the moment, when a cone is formed from a flat workpiece, which makes it possible to determine the area of workpiece destruction at the initial wrinkles. [ABSTRACT FROM AUTHOR]

In the deep drawing process of sheet metals, lack of formability and the defects generated as a consequence of friction are two main limiting factors. Using ultrasonic vibration is an impressive way to decrease these limitations. In this paper, the ultrasonic – aided deep drawing process with a novel way of applying radial ultrasonic vibration is presented. The novelty of the presented method is using the bending mode of vibration in the sheet metal and the die using radial ultrasonic vibration. The presented method, contrary to the other techniques of applying ultrasonic vibration, has shown much fewer resonance frequency variations by changing the sheet metal geometry during the process and likewise with a variation of the clearance between the blank holder and the die. For this purpose, the finite element method was used in designing the equipment for the deep drawing process. The experimental test was done on St12 in the presence and absence of ultrasonic vibration. The effect of ultrasonic vibration in the presented method on the wrinkling and thinning defects and likewise the forming forces were experimentally studied. The results indicated the high efficiency of the presenting method in decreasing both the forming forces and the wrinkling and thinning defects. About a 42.3% decrease in the forming forces and a 4.4% decrease in the thinning effect were achieved by applying ultrasonic vibration. [ABSTRACT FROM AUTHOR]

A new manufacturing process has been developed that involves drawing circular sheets of thin metal through a conical die to create square cups. This technique produces deep square cups with a height-to-punch-side length ratio of approximately 2, as well as high dimensional accuracy and a nearly uniform height. The study investigated how various factors, including the sheet material properties and process geometric parameters, affect the limiting drawing ratio (LDR). The researchers used finite element analysis to determine the optimal die design for achieving a high LDR and found that the proposed technique is advantageous for producing long square cups with high dimensional accuracy. [ABSTRACT FROM AUTHOR]

The effects of process parameters on room-temperature (RT) deep drawability were investigated for AZ31B magnesium alloy sheets, in which the formation of basal texture was suppressed by high-temperature rolling. When the blank holder force was set to the minimum value to prevent wrinkling, high RT drawability was obtained. In particular, a significantly high limiting draw ratio (LDR) of 1.83 was obtained by the optimization of the process parameters of the servo-press machine. At higher punch speeds, the drawability tended to be deteriorated; however, a high LDR of 1.72 was obtained even at a high punch speed of 50mm/s by the optimization of the process parameters of the servo-press machine. Furthermore, when the punch speed in the initial stage of deep drawing was reduced, it was possible to perform deep drawing without fracture even if the punch speed in the later stages was increased. The results of the study of the effect of lubricants indicated that relatively high RT drawability was obtained when molybdenum disulfide was utilized. It was also suggested to be important to select a lubricant that reduces punch load and does not delaminate during deep drawing. [ABSTRACT FROM AUTHOR]

The manufacturing industry heavily relies on deep drawing due to its remarkable ability to produce intricate symmetrical and asymmetrical shapes with accuracy and efficiency. This research aimed to create a deep drawing tool capable of producing a pentagonal cup measuring 41mm in diameter and 30mm in height. This was achieved by conducting numerical simulations and experimental tests using two different methods. The first method involved converting an 80mm diameter circular blank into a pentagonal cup through a drawing operation, while the second method involved redrawing a cylindrical cup into a pentagonal shape. The study also analyzed the impact of these methods on the drawing load, stress/strain distributions, and thickness distributions. The finite element method software, ANSYS 20, was employed for numerical simulations. The results showed that the first method had a significantly higher punch load than the second method. However, the pentagonal cup produced using the first method had a greater thickness reduction towards the cup wall curvature compared to those produced using the second method. Therefore, the second method was considered ideal for manufacturing a pentagonal cup because it resulted in a lower degree of thinning at the cup curvature and a more uniform distribution of thickness, stress, and strain. In conclusion, this research highlights the importance of deep drawing in the manufacturing industry and emphasizes the need to choose the appropriate forming method to achieve optimal results.

In the production of sheet metal components, batch and process fluctuations cause deviations in the resulting component properties, which often lead to production rejects. To counteract this inline, the computing time for predicting the process result and optimizing the process parameters must be very short, which is why analytical models are advantageous. A large database is usually required for modeling, and numerical simulations are well suited for generating it. The stamping velocity is a process parameter possibly varying, but strain rate dependency of the material often is neglected in numerical simulations. The objective of this study is to analyze the effects of strain rate dependent material modeling on the simulation accuracy of a sheet metal forming process. Therefore, uniaxial tensile tests and layer compression tests at different strain rates are conducted on the steel HC340LA. Based on this, the material behavior is captured in a strain rate dependent material card, which is used for the numerical simulation of a deep drawing process of a geometry with complex shape. For the validation of the model, experiments are carried out and being compared with the computational results in terms of force–displacement curves and part geometry. Furthermore, numerical investigations are used to analyze if drawbead height and blankholder force have an influence on the strain rate distribution and whether this affects the process force. [ABSTRACT FROM AUTHOR]

Ferritic stainless steel (FSS) is widely used to manufacture deep-drawn products for corrosion resistance applications, being the alloy drawability strongly affected by its microstructural anisotropy. This study combines a variety of microscopy techniques enabling in-depth analyses of the microstructural evolution of two different FSSs correlated to their deep drawing performance. One of the steels has a good correspondence with the standard EN-1.4016 (AISI 430). The other is a modified version of the previous one with higher contents of the ferrite-stabilising elements Si and Cr, and lower contents of the austenite-stabilising elements C, N, and Mn. Electron Backscatter Diffraction results confirm that the microstructural properties and drawability of FSS in the deep drawing process are improved in the modified steel version. Scanning transmission electron microscopy under low-angle annular dark field conditions evidences that the deformation mechanism of FSS during deep drawing follows a microstructural distortion model based on the grain size gradient and shows a variation of the deformation texture depending on the alloy composition. This work demonstrates the potential of advanced microscopy techniques for optimising the processing and design of ferritic stainless steels, with slight variations in the alloy composition, for deep drawing applications. [ABSTRACT FROM AUTHOR]

Deep drawing is an operation to transform flat or hollow blanks to create hollow parts of the required shape and size. Deep drawing is an essential operation in sheet-forming technology to manufacture hollow parts. These parts are commonly used in the automobile, aviation, and household appliances industries. To prevent wrinkles on the rim part, a blank holder will be used to compress and flatten the workpiece before the metal is pulled into the die by the punch. Deep drawing without using workpiece holding force is applied to form hollow parts with low depth. In this case, the mould has a simple structure, helping to reduce manufacturing time and costs and making it easier to maintain and repair. The radius of the die is an essential parameter in deep drawing; it greatly affects the quality of products (making wrinkles and tears). However, this study has shown that, in deep drawing without using a blank holder, the cone angle of the die α has a major influence on the quality of the body and rim of the products, such as the products may or may not have wrinkles, either being thinned or thickened. This cone angle also affects the drawing force. This study has determined that, with α>120°, wrinkling begins to appear in the part wall, and wrinkling tends to increase as the angle α increases. The cone angle of the die for quality products is in the range of 100° < α ≤ 120°. The taper angle smaller than 120° simultaneously increases the quality of the products and the cost of manufacturing die, so the most optimal value is determined by simulation and experimental verification as α = 120°. The results of this study can be applied to fabricate hollow cylindrical parts with similar shapes when using the deep drawing method without using the blank holder. [ABSTRACT FROM AUTHOR]

The main objective of this study was to analyze the deep drawing behavior of sandwich laminate for various blank shapes and lubrications. Commercially available aluminum sandwich laminate with face sheets made of aluminum alloy, AA2219 and a core made of high-density polyethylene was used for the forming behaviour performance. The laminate was characterized by its mass density, porosity and tensile strength for better understanding the physical and mechanical behavior, being essential for analyzing the forming behaviour. Deep drawing, one of the forming techniques on the laminate was performed with a steel spherical punch for three different blank shapes: circular, square and square with round fillets. Furthermore, three different lubricants Vaseline, grease and soap, were used at the contact regions of the die and laminate. This formation occurred under normal atmospheric conditions. Lubrication significantly influenced the drawing performance in addition to the blank shape. Uniform material flow during the drawing process was achieved in the circular specimen, which in turn resulted in better drawing performance of the laminate. The highest drawing force of 1.425 kN was obtained for the circular specimen with the grease lubricant. A higher-order equivalent plastic strain was observed for the lubricant grease, and the least-order strain was observed for the specimens under dry conditions. The higher the effect of lubrication, the lower the friction between the punch and specimen, which in turn resulted in a higher order strain and subsequent reduction in the thickness of the specimen. [ABSTRACT FROM AUTHOR]

Meso-and microforming is a technology to shape parts from extremely small metal billets. Parts with geometric dimensions are a few millimetres to a few micrometres. With the rapid development of the electrical-electronics industry and biomedical engineering, the technology of forming microscopic parts has been researched and applied because of its efficiency, accuracy, and high productivity. Deep drawing is an operation that turns flat sheet metal blanks into hollow, open-mouth parts. It is an essential process in sheet metal stamping. Micro deep drawing is one of the micro-shaping technologies that has been widely studied and applied in recent years. However, the bases for calculating technological and geometrical parameters in the micro-deep drawing have not yet been analyzed and evaluated in detail. Therefore, this paper has proposed a theoretical basis combined with simulation applied to the design of technology to manufacture a connector head part drawing die with a diameter of 300µm and height of 1500µm using materials SUS304 material. Numerical simulation also allows evaluation of the stamping part's internal stress state, the ability to pull the workpiece into the die, and the thickness distribution on the product wall. Experimental research has also verified that, with the determined parameters, the stamping parts meet the quality requirements. This indicates the proposed calculation methods for the tiny deep drawing operation are entirely suitable. The results of this research can be wholly applied to the production of micro-sized cylindrical cup parts using the deep drawing method. [ABSTRACT FROM AUTHOR]

Deep drawing processes play a pivotal role in the manufacturing of sheet and shell products, making it a widely adopted method. This research employs numerical simulations to investigate the impact of various process parameters on the fracture height of cylindrical cups made from SECC (Steel Electrogalvanized Commercial Cold rolled) material. Specifically, it examines parameters such as blank holder force (BHF), punch corner radius (Rp), die corner radius (Rd), and punch-die clearance (Wc). The study extends to optimizing fracture height, offering a solution to this challenge. Subsequently, the selected parameters are validated through experimental deep drawing of cylindrical cups, resulting in a minimal deviation of 1.55% between simulation and experiment outcomes. A precise mathematical equation is developed to estimate fracture height under diverse machining conditions, with a maximum deviation of 4.52% observed between the mathematical model and simulation. These findings represent a substantial advancement in deep drawing processes technology, particularly in reducing error rates during the production of cylindrical cups. [ABSTRACT FROM AUTHOR]

During the forming process, variations in noise parameters can negatively impact product quality. To prevent waste from these fluctuations, this study suggests a method for the in-line optimisation of the deep drawing process. The noise parameter considered is the friction coefficient, assuming the variability in lubrication conditions at the blank–tool interface. The proposed approach estimates the noise factor variability during the process by tracking the draw-in of the blank at critical points. Using this estimation, the optimal blank holder force (BHF) is calculated and then adjusted in-line to modify blank sliding and prevent critical issues on the component. For this purpose, a Finite Element (FE) model of a deep drawing case study was developed, and numerical simulation results were used to construct surrogate models while estimating both the friction coefficient and optimal BHF. The FE model's predictive capability was verified through preliminary experimental tests, and the control logic was numerically validated. Results show the effectiveness of this control type. By adjusting the BHF just once, a defect-free component is achieved. This method overcomes the limitations of feedback controls, which often need multiple adjustment steps. The time required to estimate the friction coefficient and the maximum time available for adjusting the BHF without causing defects was identified. [ABSTRACT FROM AUTHOR]

The manufacturing of three-dimensional sheet metal components, such as car body parts, heavily relies on deep drawing. With the increasing demand for lightweight measures in the automotive industry due to CO2 limitation requirements, various methods are currently employed to reduce the weight of deep drawn components. However, these methods often overlook the potential for influencing the stress-strain dependent damage state within the component, even though it can greatly affect its performance in subsequent applications, and thus offers lightweight potentials. Friction between the deep drawing tools and the sheet metal is a key factor influencing the stress-strain state, and hence, represents a lever that can be utilized to manipulate the damage state in the component. This paper focuses on the numerical analysis of the dependence of damage on friction during deep drawing. Therefore, a rectangular geometry with an asymmetrical material flow is numerically investigated. A friction ratio is introduced with different constant friction coefficients for the corner of the tools and the straight sides. The established load paths at a chosen reference point are then considered in the form of selected stress and strain characteristics and the numerically predicted damage state is compared. The results are used to derive a recommended friction ratio that leads to less damage in the corner of the geometry. Afterwards strip drawing tool surfaces are modified to manipulate their friction properties using machine hammer peening. Subsequently, the influence of the structures of the strip drawing tool surfaces is quantified using strip drawing tests. The identified contact normal stress dependent friction coefficients are then implemented in the numerical simulation and the established numerical predicted damage state is examined to gain a more comprehensive understanding of how the friction ratio and the structure of the tool surfaces influence the damage state.

Hydro mechanical deep drawing (HMDD) is an emerging technology that reduces the number of sheet-forming stages and increases the production of advanced lightweight materials with intricate shapes. This study aims to verify the springback in HMDD and the effect of holding time and fluid pressure on this phenomenon (springback). The springback was measured using a new method by matching the projector p-300 axes with the cylindrical cup wall. The difference between the wall and the axis represents the springback value. Using a blank of low carbon steel (1008-AISI) with 80 mm of diameter and a thickness of 0.7 mm. The effect of holding time (1, 2, and 3 minutes) and the fluid pressure (0.6, 0.8, and 1 N/mm2) was studied. The used hydraulic oil was (code number 3803). The springback value of a cylindrical cup was calculated using the profile projector P-300. The result showed that the springback phenomenon was presented in the hydromechanical deep-drawing process but at a lower rate than the traditional deep-drawing process. The holding time and fluid pressure significantly affected the springback value. The springback decreased with increasing the fluid pressure and holding time.

In press forming, most forming is performed cold. However, warm or hot forming is used for hard materials. In the present study, we focused on the heat generated by friction between metals and worked on the development of the warm punch that utilizes frictional heat. In the experiments, the heater jig and the rotary jig were prepared as different metals for friction. The test materials were steel materials, such as stainless steel and alloy tool steel. After frictional heating, the surface conditions of the different metals were observed by microscope. The wear depth due to friction was also measured. The temperatures generated by the rotation of the different metals differed in the time of heat generation for the combination of the two metals. In the case of stainless steel with low thermal conductivity, the temperature at the punch tip increased to around 400°C. The wear depth increased slowly with increasing time of wear in the rotary and heater jigs. The proposed method allowed the punch to be heated. The possibility of forming processing resistant material by warm deep drawing was found.