Drawing Process Research Articles

Multi-pass deep-drawing process and mould design for thin-walled hollow cylindrical parts

Thin-walled hollow cylindrical parts are widely employed in various industries, including automobiles, ships, and aviation, due to their increased demand and the escalating quality requirements for their formation. The production of these parts primarily relies on a multi-stage deep drawing process. However, during the deep drawing process, the gradual reduction in the side wall thickness creates a susceptible area at the bottom rounded transition, where local over-thinning may occur, thereby increasing the risk of cracking. Furthermore, the deep-drawing process becomes more intricate for thin-walled hollow cylindrical parts with a large height-to-diameter ratio, amplifying the likelihood of defects during actual production. This paper combines CAE simulation and empirical design to comprehensively investigate and analyze the multi-stage deep drawing process and mold design for thin-walled hollow cylindrical parts. The aim is to optimize the deep-drawing process and mold parameters, enhance the products qualification rate, and provide valuable guidance for the practical production of relevant enterprises.

Membangun Budaya Kerja Yang Mendukung Kinerja Tinggi

This study aims to explain the role of organizational culture in enhancing employee performance in a company. A qualitative approach with a literature review is used as the research methodology, while data collection techniques are conducted through documentary studies. The collected data is then processed through the process of reduction, presentation, and conclusion drawing. The research findings indicate that organizational culture is formed from the implementation of values, norms, and policies by organizational leaders, while employee performance is measured based on their work results in completing organizational tasks. The role of organizational culture in improving employee performance includes aspects of innovation, attention to detail, benefit orientation, individual orientation, team orientation, aggressiveness, and job stability. This is beneficial in shaping work habits that align with the standards set by the organization; therefore, leaders need to propose ideas or policies that can shape the desired work culture.

Correction to: Application of ML methods to predict residual stresses and strains after wire drawing process

Correction to: Application of ML methods to predict residual stresses and strains after wire drawing process

Self-Poled Piezoelectric Nanocomposite Fiber Sensors for Wireless Monitoring of Physiological Signals.

Self-powered sensors have the potential to enable real-time health monitoring without contributing to the ever-growing demand for energy. Piezoelectric nanogenerators (PENGs) respond to mechanical deformations to produce electrical signals, imparting a sensing capability without external power sources. Textiles conform to the human body and serve as an interactive biomechanical energy harvesting and sensing medium without compromising comfort. However, the textile-based PENG fabrication process is complex and lacks scalability, making these devices impractical for mass production. Here, we demonstrate the fabrication of a long-length PENG fiber compatible with industrial-scale manufacturing. The thermal drawing process enables the one-step fabrication of self-poled MoS2-poly(vinylidene fluoride) (PVDF) nanocomposite fiber devices integrated with electrodes. Heat and stress during thermal drawing and MoS2 nanoparticle addition facilitate interfacial polarization and dielectric modulation to enhance the output performance. The fibers show a 57 and 70% increase in the output voltage and current compared to the pristine PVDF fiber, respectively, at a considerably low MoS2 loading of 3 wt %. The low Young's modulus of the outer cladding ensures an effective stress transfer to the piezocomposite domain and allows minute motion detection. The flexible fibers demonstrate wireless, self-powered physiological sensing and biomotion analysis capability. The study aims to guide the large-scale production of highly sensitive integrated fibers to enable textile-based and plug-and-play wearable sensors.

Form and functioning: contextualising the start of the Global Financing Facility policy processes in Burkina Faso

ABSTRACT Background Burkina Faso joined the Global Financing Facility for Women, Children and Adolescents (GFF) in 2017 to address persistent gaps in funding for reproductive, maternal, newborn, child, and adolescent health and nutrition (RMNCAH-N). Few empirical papers deal with how global funding mechanisms, and specifically GFF, support resource mobilisation for health nationally. Objective This study describes the policy processes of developing the GFF planning documents (the Investment Case and Project Appraisal Document) in Burkina Faso. Methods We conducted an exploratory qualitative policy analysis. Data collection included document review (N = 74) and in-depth semi-structured interviews (N = 23). Data were analysed based on the components of the health policy triangle. Results There was strong national political support to RMNCAH-N interventions, and the process of drawing up the investment case (IC) and the project appraisal document was inclusive and multi-sectoral. Despite high-level policy commitments, subsequent implementation of the World Bank project, including the GFF contribution, was perceived by respondents as challenging, even after the project restructuring process occurred. These challenges were due to ongoing policy fragmentation for RMNCAH-N, navigation of differing procedures and perspectives between stakeholders in the setting up of the work, overcoming misunderstandings about the nature of the GFF, and weak institutional anchoring of the IC. Insecurity and political instability also contributed to observed delays and difficulties in implementing the commitments agreed upon. To tackle these issues, transformational and distributive leaderships should be promoted and made effective. Conclusions Few studies have examined national policy processes linked to the GFF or other global health initiatives. This kind of research is needed to better understand the range of challenges in aligning donor and national priorities encountered across diverse health systems contexts. This study may stimulate others to ensure that the GFF and other global health initiatives respond to local needs and policy environments for better implementation.

Effect of bismuth on the mechanical properties and microstructure evolution of iron matrix during drawing: a molecular dynamics study

This paper investigates the effects of bismuth nanoparticles on the mechanical properties and microstructure evolution of single-crystal iron matrix materials during the drawing process using molecular dynamics methods, and also explores the effects of different drawing speeds and loading methods on the drawing process. The results show that the incorporation of bismuth nanoparticles has a significant effect on the axial drawing force, dislocation, shear strain and crystal evolution during the drawing process. When the bismuth nanoparticles started to deform under the action of drawing force, the atomic shear strain and crystal evolution were concentrated around them, which hindered the generation of dislocations and led to the reduction of their axial drawing force. In addition, the degree of atomic shear strain and crystal evolution increases with the increase of drawing speed, leading to work hardening of the material, and thus increasing the axial drawing force. Finally, when the loading mode is positioned at the rear end, shear strain becomes more concentrated around the bismuth nanoparticles, hindering dislocation generation and increasing the material’s hardness and axial drawing force. This study is important for understanding the mechanism of bismuth nanoparticles on the iron matrix of single-crystal during the drawing process.

Nonlinear radiative thermal analysis of magneto-micropolar fluid over a bidirectionally extending sheet with varied thermal conditions

Thermal fluid flow analysis occasioned by stretching surfaces offers practical industrial and engineering applications, such as extrusion and drawing processes and materials experiencing heating and cooling conditions. Thus, this study explores magnetohydrodynamic micropolar fluid flow under varied thermal conditions and nonlinear thermal radiation over a dually stretched sheet subject to surface mass flux and an internal heat source. The study thus provides insight into the dynamics of heat transfer mechanisms for improving material processing techniques in many engineering processes. The flow dynamics with the thermal analysis are evaluated by applying two thermal conditions in the heat equation: the prescribed surface temperature (PST) and the prescribed heat flux (PHF). The formulated partial derivative equations that describe the current problem are changed into ordinary derivatives using some similarity quantities, while the converted equations are tackled with the combined techniques of shooting and Runge–Kutta Fehlberg. Consequently, diverse tables and figures are displayed to deliberate on the impacts of the physical terms on the dynamics of flow and heat transmission processes. The consequence of the analysis reveals a higher heat gradient in the prescribed surface temperature case than the uniform temperature distribution, as the Prandtl number magnifies. The micropolar material term reduces the surface frictional factor and depletes heat transmission, but the magnetic field term raises the skin friction coefficient.

THE SIMULATION OF THE ANISOTROPY OF ALUMINUM ALLOY SHEETS BY DEEP DRAWING: A CRUCIAL STUDY FOR THE AUTOMOTIVE AND MATERIALS ENGINEERING INDUSTRIES

Recently, the automotive industry has shown an increasing interest in utilizing thin aluminum alloy sheets to reduce the weight of various car components. The occurrence of uneven cup heights in deep drawing processes is called earing. This issue arises due to the planar anisotropy of sheets, a consequence of crystallographic texture. Therefore, this study involves a meticulously conducted cylindrical cupping test. For the experimental research, four different aluminum alloys were used, each with distinct mechanical and plastic properties. The experimental results of the drawing process were compared with the simulation results using the Simufact Forming software. Different numbers of elements were selected for experimental material with a 1 mm thickness to further compare the simulation results with experiments. In a separate simulation in the Simufact Forming software, the effect of the number of elements on the earing height and computing time was evaluated. The results obtained with five different solvers were compared within Simufact Forming. The results showed significant differences in computing times for the different types of solvers.

Prior semantic-embedding representation learning for on-the-fly FG-SBIR

In fine-grained sketch-based image retrieval (FG-SBIR) framework, sketch drawing is a time-consuming and skill-intensive process that greatly restricts its practical application. Our study aims to enhance the early-stage retrieval efficiency by utilizing partial sketches with a minimum number of strokes in the on-the-fly FG-SBIR framework. Nevertheless, partial sketches with few strokes usually lack global information and consist only of sparse local details. This lack of detail results in ambiguous semantic content and indistinct differences among images, which consequently impairs early-stage retrieval. To acquire an efficient representation for these sketches, we propose a multi-granularity feature representation model that utilizes prior knowledge embedding to deal with the sketch drawing process. In the first stage,we design a triplet network to learn the joint a coarse representation embedding space that is common between the complete sketch and the image. In the second stage, We enhanced the semantic representation of sketches by utilizing prior knowledge, which aids in supplementing missing fine-grained features. This was achieved by formalizing the prior knowledge and integrating it into the feature vector obtained in the initial stage, thereby acquiring the final representation of a subset of sketches. Experiments conducted on two public datasets indicate that our method outperforms the state-of-the-art baseline during the early retrieval phase. In practical applications, our approach has also achieved good results.

Excellent thermal conductive epoxy composites via adding UHMWPE fiber obtained by hot drawing method

AbstractThe continuous updating and iteration of electronic devices brings about a significant accumulation of heat. It is urgent to enhance the thermal properties of polymer‐based composites to alleviate the heat dissipation problem in the microelectronics industry. In this paper, the hot drawing process was introduced to increase the crystallinity of ultra‐high molecular weight polyethylene (UHMWPE) fiber and improve its thermal conductivity. The ultra‐high molecular weight polyethylene fiber/epoxy resin (UHMWPE fiber/Epoxy) composites with high thermal conductivity were prepared by compositing UHMWPE fiber with epoxy resin under vacuum conditions. Due to the good crystallinity of the UHMWPE fiber (86%), an efficient thermal conduction path is provided for phonons in the axial direction along the fibers. The results show that the thermal conductivity of the composites reaches a maximum of 3.51 W/mK (in‐plane), which is 17.47 times higher than that of the epoxy resin (0.19 W/mK). The thermography pictures indicate that the composites have better heat transfer capacity with an increase in the draw ratio (λ). In addition, the composites also have the characteristics of low density and low electrical conductivity. These researches will provide a new idea for the preparation of all‐polymer composites with high thermal properties.Highlights A hot drawing process was introduced to increase the crystallinity of UHMWPE fiber for improving thermal conductivity. High crystallinity facilitates the reduction of phonon scattering and the transmission of thermal energy by phonons. The obtained polymer composites exhibit an ultra‐high in‐plane thermal conductivity.

Application of ML methods to predict residual stresses and strains after wire drawing process

Application of ML methods to predict residual stresses and strains after wire drawing process

A Study on Yield Criteria Influence on Anisotropic Behavior and Fracture Prediction in Deep Drawing SECC Steel Cylindrical Cups.

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.

Enhanced Strength–Ductility Synergy of Mg–6Zn Alloy Wire by Inducing Guinier–Preston Zone Precipitation

This article designs a strategy of introducing ultrafine precipitates into single‐phase microstructure to enhance Mg–6Zn alloy wire. Three combined processes including equal channel angular pressing (ECAP), direct extrusion, and multipass drawing are used to produce 0.3 mm‐diameter wire. The results show that an isothermal process of ECAP, extrusion, and drawing at 32 °C (named route B) produces a near‐fully solid solution microstructure and causes a very high elongation of 21% as well as an ultimate tensile strength of 24 MPa. Furthermore, on this basis, the addition of an aging treatment before drawing induces the precipitation of the Guinier–Preston zone in the near‐single‐phase Mg matrix and improves the tensile elongation to 28%, and the ultimate tensile strength also is increased to 290 MPa.

Modeling Analysis of Complex Deformation of Woven Coating Film during the Cyclic Tensile Process.

It is difficult for the existing Burgers model to accurately depict the off-axis cyclic drawing process of woven coatings. In this paper, the mechanical deformation of woven PVC (polyvinyl chloride)-coated film at different temperatures is investigated. One-dimensional (1D) and two-dimensional (2D) constitutive models were established to characterize cyclic deformation processes. The 1D model is an improved Burgers model. The effects of the time dependence of the viscosity coefficient and the ratio of elastic to viscous deformation are considered simultaneously. The accuracy of the 1D model for predicting the cyclic nonlinear deformation at different temperatures and loading rates is improved. The 2D model is a nonlinear orthotropic model using polynomials. On the basis of the single-objective genetic algorithm, the inverse algorithm is used to obtain the shear polynomial coefficients in the tension phase and the shear modulus in the unloading phase, which circumvents performing the difficult shear test. UMAT subroutines of off-axis stretching and off-axis cyclic stretching are written separately. The intelligent inverse algorithm program consists of a single-objective genetic algorithm program, a finite element parametric modelling program, and a UMAT subroutine. The simulation results are compared with the off-axis cyclic tensile test data to validate the effectiveness and accuracy of the proposed 2D model for the analysis of the woven PVC-coated films in the tension-shear coupling state.

Optimization and experimental evaluation of the Al1100 and SS202 cylindrical cups using conical die without blank holder

Deep drawing is the most widely used process for forming cup shaped products in automobile, aerospace, and packing industries. In this research, the deep drawing process is used to draw the cylindrical cups of Al1100 and SS202 metal sheets using a new type of conical die and a flat-bottomed punch without a blank holder. The experiment included in this work used blank diameters of 50, 55, 60, and 70 mm, tested under both dry and lubricated conditions. The findings indicated that the lubrication significantly reduced defects such as deflection, spring-back, earing, and uneven depth. A blank diameter of 60 mm is optimal for defect-free cups. In addition, the research observed that lower friction coefficients corresponded to required load. The deep drawing procedure has distinctive effectible process parameters from which an optimum level of parameters and defect-free cups with required mechanical properties can been obtained. Thus, using the mixed response surface methodology for optimization, the research showed an excellent decrease in the maximum required load, mainly under lubricated conditions. In brief, the optimization model for SS202 under dry conditions became incredibly accurate, with less than 1% error compared to experimental results. On the other hand, for Al1100 under dry conditions, the model’s predictions deviated more, showing more than a 12% error, indicating a need for additional refinement or extra factors to enhance the accuracy of Al1100.

Experimental and Analytical Investigation of the Ceep Drawing Process for producing Pentacle Cups

Experimental and Analytical Investigation of the Ceep Drawing Process for producing Pentacle Cups

Research Report of the Creative Inspiration of Oil Painting Landscape in Northwest China

The landscape has regional characteristics, rich landform changes and distinct seasons, which provides a good inspiration for artistic creation. This study collects and collates landscape materials through field investigation; the system analysis method is used to study the creative drawing process and artistic characteristics of oil painting landscape in Northwest China. Summarize the importance and flexibility of creative inspiration. The study found that creative inspiration is flexible and diverse, fleeting, and requires the artist’s keen insight to capture. This study provides theoretical support for further research on the inspiration of oil painting character creation.

Implementasi Media Digital Berbasis Quizizz Pada Mata Pelajaran Sejarah Kebudayaan Islam di MAN 2 Wonosobo

Over time, schools have adopted various learning technologies, one of which is the use of quiz-based media. Quizizz is an educational platform that presents learning in a gaming format, utilized as a tool for educating students. However, due to its proven benefits in education, especially in the subject of Islamic Cultural History, teachers at Madrasah Aliyah Negeri 2 Wonosobo continue to opt for its use in their teaching. The objectives of this research are: (1) To understand the Quizizz-based digital media in teaching Islamic Cultural History at MAN 2 Wonosobo, (2) To understand how teachers develop Quizizz-based digital media in the subject of Islamic cultural history at MAN 2 Wonosobo, (3) To understand the implications of Quizizz-based digital media in teaching Islamic cultural history at MAN 2 Wonosobo. The research method applied in this study is qualitative with a descriptive approach. This approach involves the use of observation methods, interviews, content analysis, and other data collection techniques. The study was conducted in the environment of Madrasah Aliyah Negeri 2 Wonosobo. After the data collection, data analysis was carried out, including the processes of reduction, presentation, and conclusion drawing. The findings of the study indicate that teachers have utilized the Quizizz digital platform in teaching Islamic Cultural History at MAN 2 Wonosobo, and students have responded positively. The study also illustrates that the utilization of Quizizz in teaching Islamic Cultural History at MAN 2 Wonosobo has proven to be quite successful, although there are some challenges that need to be addressed.

Stearate from Steel Wire Drawing Processes as a Resource

STAR (Stearato dai processi di Trafilatura del filo di Acciaio come Risorsa) project, funded by the Italian Ministry of the Environment, has the ambition of redesigning the use and life cycle of waste stearates from the steel wire drawing industry, promoting the circular life of such materials. Waste stearate is having a strong impact on the economic and environmental sustainability of the steel wire production processes, adding up to the increasing pressure that industry has been facing in the last years: the pandemic crisis, the raw material price increase, the commercial restrictions related to the Ukraine and other regional conflicts.The short-term goal of the project is to develop a technology to be applied on a local scale and the long-term one is expanding it internationally. The benefits are both environmental, due to the reduction of waste and related impact on the environment, and economic, due to stearate valorization.First, stearate waste from wire drawing process were characterized in order to valorize them in the production of new materials or as an energy source.Samples of stearate waste were provided by wire drawing industries and the analyses showed that the humidity content was always low (0.1 – 5 %), while the volatile solids (VS) content varied from 2 to 70%, covering a very wide range and thus indicating a variable organic matter content. The mean higher heating value was 26 MJ/kg and the Chemical Oxygen Demand (COD) 500 mg O2/g and correlated well with VS. pH was strongly basic (>11).Anaerobic digestion can surely have an important role in valorization, as it allows to recover energy and to produce a stabilized digestate for which a further use can be studied, according to its properties. Preliminary BMP tests (BMP = Biomethane Potential) determined a biomethane production in the range 500-900 L/kgVS, much higher than the production from animal waste (around 400 L/kgVS). The toxicity of the digestate was assessed by Microtox® assay and was negligible. This finding supports the hypothesis that recalcitrant compounds, which do not undergo degradation in anaerobic conditions, are not toxic.

Child’s artistic creativity – zone of immediate development – trajectories of abilities

Artistic creativity of a child, as it is known, is a proper form of expression, communication,and the development of abilities. It is a necessary condition for the child’s developmentto proceed wholly and to educate a healthy and mentally balanced person. Looking at thechild’s artistic creativity as a process, I adopt a psychological approach to the pedagogy ofa child’s creativity, which emphasises the dynamics and development of the child’s cognitiveprocesses and is even more promising in explaining the mechanisms of children’sartistic creativity. The approach to drawing children as a developmental process allowedme to adopt the thesis of Lev S. Vygotsky (1989) on the ‘developmental point of view’to explain the drawing process and its moments and the ‘zone of the child’s proximaldevelopment’. Based on my previous research (Szuścik, 2006) on the formation of thesphere of meaning in a child’s drawing and its complexity, I will present a proposal for anapproach to the analysis of a child’s artistic creativity in the context of the concept of L.S.Vygotsky’s zone of proximal development and the trajectory of abilities. I present a modelfor developing a child’s artistic creativity, considering the zone of proximal development.