Showing papers on "Material flow published in 2011"
TL;DR: In this paper, the effect of joining parameters on the mechanical properties, microstructural features and material flow of dissimilar aluminium alloys (3mm-thick AA2024-T3 and AA7075-T6 sheets) joints produced by friction stir welding was evaluated.
172 citations
TL;DR: A seamlessly integrated information management framework that can provide logistics information to project stakeholders for their decision making is developed and showed that it can improve time efficiency by about 32% compared to the traditional supply chain management.
144 citations
15 Aug 2011-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
TL;DR: In this article, a thermo-mechanical simulation of the friction stir processing (FSP), using the DEFORM 3D software based on Lagrangian implicit, was developed and verified by the experimental results.
Abstract: A thermo-mechanical simulation of the friction stir processing (FSP), using the DEFORM 3D software based on Lagrangian implicit, was developed and verified by the experimental results. Simulation can successfully predict the temperature and effective strain distributions. Material flow around the tool pin was examined using the point tracking. It was found that the major part of material flow occurs at the advancing side, and consequently, stirred zone (SZ) stretches toward the advancing side. However, material at the retreating side moves slightly in backward direction. The material deformation and the peak temperature influence on the microstructural characters and can determine the width of SZ. Based on the simulation, effective strain and temperature histories of material around the tool pin were also calculated. The amount of effective strain and peak temperature required for recrystallization at the advancing and retreating sides as well as at the bottom of SZ was determined. Therefore, the width of SZ can be predicted by the simulation.
116 citations
TL;DR: In this article, the movement of a spherical tungsten tracer during friction stir welding is observed by two pairs of X-ray transmission real-time imaging systems, and the three-dimensional material flow is obtained by following the locus of the tracer.
104 citations
TL;DR: In this article, a comparison and observations on material flow patterns in planewedged, space-wedged and flat-bottomed hoppers were accounted for by using the discrete element method (DEM).
90 citations
TL;DR: In this article, a general-purpose tooling set for realization of micro-forward, backward, combined forward rod-backward can and double cup extrusions is developed and the micro-extrusions of pure copper with different grain sizes are analyzed based on the deformation load, interfacial friction behavior and microstructure evolution.
90 citations
TL;DR: In this paper, a thermomechanical modeling of the material flow is developed, and the tool-chip contact length and the sliding-sticking zones are characterised analytically.
72 citations
TL;DR: In this article, structural decomposition analysis (SDA) is applied to the change in raw material consumption (RMC) of the Czech Republic between 2000 and 2007, showing that the largest relative increases are reported for non-iron metal ores (38%) and construction materials (30%).
Abstract: Summary
The aim of this article is to quantify the drivers for the changes in raw material consumption (domestic material consumption expressed in the form of all materials extracted and used in the production phase) in terms of technology, which refers to the concept of sustainable production; the product structure of final demand, which refers to the concept of sustainable consumption; and the volume of final demand, which is related to economic growth. We also aim to determine to what extent the technological development and a shift in product structure of the final demand compensate for the growth in final consumption volume. Therefore, we apply structural decomposition analysis (SDA) to the change in raw material consumption (RMC) of the Czech Republic between 2000 and 2007. To present the study in a broader context, we also show other material flow indicators for the Czech Republic for 2000 and 2007.
Our findings of SDA show that final demand structure has a very limited effect on the change in material flows. The rapid change in final demand volume was not compensated for crude oil, metal ores, construction materials, food crops, and timber. For the material category of non-iron metal ores, even the change in technology contributes to an increase in material flows. The largest relative increases are reported for non-iron metal ores (38%) and construction materials (30%).
The main changes in material flows related to the Czech Republic are driven by exports and enabled by imports, the main source of these increased material flows. This emphasizes the increasing role of international trade.
62 citations
TL;DR: In this article, a material constitutive model was established based on microcompression test and its applicability was then studied, and the applicability of the calibrated flow stress strain curve was finally validated by the experimental and simulation results of micro-forward extrusion.
51 citations
TL;DR: In this article, the effect of the Alclad layer on material flow and defect formation during friction-stir welding (FSW) of 6.5mm-thick 2024Al-T351 alloy plates was investigated.
Abstract: The effect of the Alclad layer on material flow and defect formation during friction-stir welding (FSW) of 6.5-mm-thick 2024Al-T351 alloy plates was investigated. To characterize the material flow during FSW, different cross sections of the keyhole and “stop-action weld” were made for metallographic observations. It was found that the top Alclad assembled at the shoulder/workpiece interface, thereby weakening the material flow in the shoulder-driven zone and favoring the formation of void defect at high traveling speeds. The bottom Alclad layer extended into the weld at excess material flow state, which could be avoided at balanced material flow state. A conceptual model of material flow was proposed to describe the formation of the weld. It was indicated that a perfect FSW joint of Alclad 2024Al alloy without defect could be obtained at an optimum FSW condition.
50 citations
TL;DR: In this paper, all production steps in the manufacture of disks made of SAE 5120 prior to heat-treatment were analyzed by means of design of experiments (DoE) and the influence of hardenability, pre-heat treatment, forging temperature, and feed rate and partition of material removal in cutting on the distortion of disks were investigated.
Abstract: In order to minimize shape deviations in hardening of gear wheels, all production steps in the manufacture of disks made of SAE 5120 prior to heat-treatment were analyzed by means of design of experiments (DoE). The influence of hardenability, pre-heat treatment, forging temperature, and feed rate and partition of material removal in cutting on the distortion of disks were investigated. Standard case hardening of the disks led to a characteristic shape change called “dishing”. The statistical analysis of the test results has proven that dishing of disks is mainly affected by the partition of the material removal in the considered case. In additional experiments dishing could be eliminated (on average) by an optimized partition of the material removal. However, results from experiments with spray-formed disks and with disks using a different forming strategy imply that the material flow combined with material inhomogeneities are the physical causes for dishing rather than the partition of material removal.
TL;DR: In this article, experimental flow curves of Ti-6Al-4-V alloy were obtained using the isothermal hot compression test done at 750-950°C with 50°C intervals and constant strain rates of 0.001, 0.005 and 0.01 s−1.
TL;DR: In this paper, the effect of different process parameters on the flow balance and temperature evolution of the extruded sections is shown and discussed, and the effects of an undesired lateral temperature gradient in the billet on the exit velocity of the aluminium sections are discussed.
01 Jan 2011
TL;DR: In this article, the authors discuss the material flow cost accounting as a potential approach to reveal the quantitative and monetary effects in the frame of material flow management, and present two enhancements for improvement: the explicit regard of energy (loss) flows and a procedure for a more detailed analysis and forecast of system costs.
Abstract: There is no doubt about the need for a sustainable production. However, the development of resource saving process designs raises the question how to appraise the economic effects of appropriate alternative process (chain) configurations and technologies. The paper discusses the material flow cost accounting as a potential approach to reveal the quantitative and monetary effects in the frame of material flow management. It gives an introduction to its basic ideas, identifies methodical shortcomings and presents two enhancements for improvement: the explicit regard of energy (loss) flows and a procedure for a more detailed analysis and forecast of system costs.
TL;DR: In this article, the performance of four material model sets of the Johnson-Cook constitutive equation in modeling the deformation behavior of Ti6Al4V alloy is compared with results from orthogonal cutting experiments on a tube of the work material.
Abstract: The machining of titanium alloys poses several inherent difficulties owing to their unique mechanical properties and cutting characteristics. Finite element (FE) simulations have reduced the burden of extensive experimental trials in understanding the deformation behavior and optimize the cutting process. The FE code relies on the qualitative nature of inputs such as material flow stress model, friction conditions, fracture criterions and the accuracy of the modeling process. The aim of this paper is to assess the performance of four material model sets of the Johnson-Cook (JC) constitutive equation in modeling the deformation behavior of Ti6Al4V alloy. The FE output at steady state conditions is compared with results from orthogonal cutting experiments on a tube of the work material. The effect of the parameters of the JC law and the capabilities of the constitutive equation are analyzed. The FE model is excellent in predicting the effective stress, strain and temperature, but produces marginal deviations in cutting force and chip morphology predictions and under predicts the feed forces. The material model constants computed through an evolutionary computational optimization process and those with conditions similar to machining produced good correlation with experiments.
TL;DR: A new friction model is developed, taking into account the sliding velocity between tools and workpiece, and it is confirmed that this model represents the state of the art in tribology.
Abstract: The finite element method is a powerful tool for the design and optimization of hot forming processes. In order to obtain high accuracy in simulation results, exact knowledge of the process conditions is required. Due to the fact that friction in the contact area has a significant impact on the material flow during the forming process, a realistic description of this boundary condition in the FE simulation is important for the usability of the simulation results. The most important influencing factors are the contact pressure, the roughness of the contact surfaces, the sliding velocity and the flow behavior of the material. Currently, only constant friction coefficients are considered in commercial finite element systems for the simulation of bulk metal forming processes. However, this description does not represent the state of the art in tribology. A new friction model is developed, taking into account the sliding velocity between tools and workpiece. This is confirmed by experimental and numerical investigations on model experiments and industrial process.
TL;DR: In this article, the top and bottom layers of a friction-surfaced coating were studied using tungsten powder as a marker, and it was shown that the material transport of material takes an involute path and the material transfer starts from the advancing side of the coating to the retreating side and terminates at the center.
Abstract: Metal flow behavior within friction surfaced coating was studied using tungsten powder as a marker. The results show that the top and bottom layers within the coating exhibit distinct flow patterns. The transport of material takes an involute path, and the material transfer starts from the advancing side of the coating to the retreating side and terminates at the center. The recirculation of material occurs at the retreating side of the coating.
Patent•
01 Jun 2011
TL;DR: In this paper, an image recording unit has at least two image detectors for recording images or image series of the crop material flow at equidistant intervals or permanently, wherein one of the image detectors is disposed substantially perpendicularly to a top side of a surface of the grain elevator head or a discharge chute.
Abstract: A device for detection and determination of a composition of a bulk material, has an image recording unit, at least one control unit, at least one memory unit, and a selection unit to enable a qualified determination to be made, during a transfer of a crop material flow into a container of an agricultural harvesting machine, of a composition of a crop during processing of the crop material, so that adjustment parameters of working assemblies of the agricultural harvesting machine are changeable during the processing of the crop material, wherein the image recording unit has at least two image detectors for recording images or image series of the crop material flow at equidistant intervals or permanently, wherein one of the image detectors is disposed substantially perpendicularly to a top side of a surface of the crop material flow emerging from a grain elevator head or a discharge chute, and another one of the two image detectors is disposed substantially perpendicularly to an underside of a surface of the crop material flow
17 Oct 2011
TL;DR: In this article, a fuzzy control method was proposed to improve the energy efficiency of belt conveyors in industrial material transport and logistics distribution by applying fuzzy logic to represent the alteration of material flow scenarios.
Abstract: Belt conveyors are widely applied for industrial material transport and logistics distribution. In general, belt conveyors run at nominal belt speed. The belt can be only partly filled when received material flow is smaller than the nominal conveying capacity. Researches have shown that conveyor speed control always leads to the reduction of the required electrical drive power. Current applications mainly focus on developing control models and implementing controllers for continuous speed adjustment. However, for practical reasons discrete control is preferred. This paper presents a fuzzy control method to improve the energy efficiency in material transport. This method applies fuzzy logic to represent the alteration of material flow scenarios. Fuzzy control algorithm provides optimal adjustment of belt speed to avoid potential material spillage and overload caused by short-term peaks of material loading rate. The improvement of energy efficiency is estimated by both simulation and practical measurement.
TL;DR: In this paper, a modular tool concept was developed to prepare and visualize the material flow inside a porthole die for aluminum extrusion processes and the results of the experimental analysis were used for the verification of numerical results calculated with the commercial software codes Deform3D and HyperXtrude.
Abstract: The design of porthole dies for aluminum extrusion processes is very complex. For the accurate design, fundamental knowledge about material flow is of major importance. To gain these information, numerical methods are increasingly utilized. The accuracy of the simulation results depends mainly on the precision of the used boundary conditions in the model. Therefore, visioplastic analyses of the material flow inside a porthole die are presented in this paper. A special modular tool concept was developed to prepare and visualize the material flow inside the process. The results of the experimental analysis were used for the verification of numerical results which were calculated with the commercial software codes Deform3D and HyperXtrude.
Journal Article•
TL;DR: In this paper, a series of compression tests were simulated using Abaqus software and deviations between the deformation curves and the material flow curves were analyzed using Taguchi approach, and the final shape of samples and friction coefficients were logically correlated.
Abstract: In the hot compression test friction has a detrimental influence on the flow stress through the process and therefore, correcting the deformation curve for real behavior is very important for both researchers and engineers. In this study, a series of compression tests were simulated using Abaqus software. In this study, it has been employed the Taguchi method to design experiments by the factors of material flow curve and the friction coefficient. The compression test was simulated up to the axial strain of 1 and then the deformation curve was extracted from the force-displacement plot of the strokes. Deviations between the deformation curves and the material flow curves were analyzed using Taguchi approach. Furthermore, the final shape of samples and friction coefficients were logically correlated. As a result, a new method was proposed in order to evaluate the material flow curve, based on the experimental data by the mathematical data manipulation..
TL;DR: The improved analytical methodology based on the identification of decommissioning materials, definition of detailed material streams, development of scenarios, calculation of output parameters and final optimization, is presented and the summarizing conclusions and recommendations are presented.
01 Jan 2011
TL;DR: In this article, the problem of discontinuous work flow in pulley plant resulting from the plant layout was investigated and the problem in terms of material flow of each operation section was indentified.
Abstract: This research aims to improve the plant layout of pulley's factory to eliminate obstructions in material flow and thus obtain maximum productivity. The present plant layout and the operation process of each section (i.e. sand mold, core ware house, core making, disassembly surface finishing, furnace, and inspection sections) have been investigated. The problem in term of material flow of each operation section was indentified. The result showed that disassembly surface finishing and inspection sections should be allocated to make the good material flow. The suitable of new plant layout can decrease the distance of material flow, which rises production. plant layout design for denture manufacturing. The suitable 4 plant layout models were designed and compared the efficiency of each plant by adjacency-based scoring. Moreover, line balancing was done to allocate human resource by using simulation programming (Arena 10) to find the increasing productivity of the new improvement layout. These thus reflect the importance of the plant layout design to bring about an increase in productivities. Yet, plat layout design is complicated due to many related factors such as employees, workflow, machine positions, and the relationship between machines and work. These factors result in plant layout improvement planning. Moreover, investment is required for machine positioning. Hence, the primary step for plant layout improvement should be started with indentifying the problems of the current plant layout in order to maximize the productivities at the minimized investment. This research therefore aims to find out the causes of discontinuous work flow in pulley plant resulting from the plant layout. The researchers of this research have studied on the problems occurred to improve the plant layout and minimized the budget for the improvement.
TL;DR: This research proposes an enhanced conceptual model for Personalized Material Flow Services for consumer behavior based on X-Party Material Flow theory for which the concept of virtual collector, information filter and Material Flow coordinator are discussed.
Abstract: A growing concern about the consumer behavior in Internet economy has spurred the study of Material Flow, resulting in a unique type of consumer behavioral analysis. This research proposes an enhanced conceptual model for Personalized Material Flow Services for consumer behavior. In the era of Internet information technology, customer's taste tends to be personalized for their market demand. It is observed that there are number of "Long Tail" phenomena in several successful e-commerce business cases. However, the Long Tail phenomenon is an open question for our research in terms of its role in e-commerce marketing. In the proposed model-X-Party Personalized Material Flow Services, three elements are discussed. They are "providing", "locating" and "obtaining" based on X-Party Material Flow theory for which the concept of virtual collector, information filter and Material Flow coordinator are discussed. Business examples of Amazon, Dangdang and Taobao are used to analyze the elements of the virtual collector, information filter and Material Flow coordinator of the Personalized Material Flow Service system.
TL;DR: In this article, the authors presented theoretical analysis of a three-slide forging process of hollowed shaft from Ti-6Al-4V alloy in a 3D forging press.
Abstract: This paper presents theoretical analysis of unconventional forging process of hollowed shaft from Ti-6Al-4V alloy in a three-slide forging press. This method in comparison with other metal forming methods allows for obtaining of hollowed products. The designed process is verified theoretically by means of numerical simulations based on finite element method with assumption of 3D state of strain. The following factors are considered in the analysis: material flow kinematics, strain distribution, temperature distribution and force of process. On the basis of results, it is stated that the application of designed technology allows for obtaining of a product of assumed quality. A comparison is made between material consumption in analyzed process and material consumption in typical metal forming methods, also in used at present technology of shaft manufacturing by machining only. It is stated that the application of forging in the three-slide forging press allows for a considerable decrease of manufacturing costs due to material savings and decrease of labor consumption of operations at finishing.
07 Nov 2011
TL;DR: A system dynamics model is presented to describe the disaster-relief supply chain under dynamic transport and information delays and results indicate that the transport delay influences the material flow directly, while the information delay impacts the system in multiple ways.
Abstract: In the disaster-relief operations, the emergency supplies usually suffer heavy and dynamic transport delay and information delay. The mechanism of how those delays influence the material flow and information flow is relatively less studied. In this paper, a system dynamics model is presented to describe the disaster-relief supply chain under dynamic transport and information delays. Three levels of each delay are generated respectively and nine scenarios are cross-constructed from them. The simulation results indicate that the transport delay influences the material flow directly, while the information delay impacts the system in multiple ways. Furthermore, two enhanced inventory desiring methods trying to suppress those impacts are discussed. The improvement of performance points out that both the level and the fluctuation of transport delay are affecting the final supply level.
TL;DR: In this article, the effect of initial billet diameter, number of spline teeth, and die corner radius on the required forging load, pattern of material flow, and effective strain distribution was analyzed.
Abstract: This article presents numerical and experimental study of spline production with an injection forging process, in terms of load requirement and material flow. A three-dimensional finite element model has been developed to analyze the effect of initial billet diameter, number of spline teeth, and die corner radius on the required forging load, pattern of material flow, and effective strain distribution. For this purpose, the finite element-based DEFORM-3D software has been used. Also, a series of experimental tests has been carried out using solid commercial lead billets with two different billet diameters and three different die cavities (two, three, and six teeth). The results obtained using the numerical solutions were compared with the experimental data for each case study and good agreement was observed. Both the simulation and experimental results highlight the major role of the above-mentioned parameters on the required forming load and material flow pattern. It has been shown that the initial bille...
25 Apr 2011
Patent•
03 Feb 2011
TL;DR: In this article, the authors present a system and method for monitoring the flow of materials used to mark road surfaces and other surfaces, which utilizes one or more pressure sensors to monitor in-line pressure of road marking material.
Abstract: Presented herein are a system and method (i.e., utilities) for monitoring the flow of materials used to mark road surfaces and other surfaces. The utilities utilize one or more pressure sensors to monitor in-line pressure of road marking material to determine the amount of material being applied. Electronic equipment receives signals from the pressure sensors, temperature sensors and/or additional monitoring equipment to generate an output indicative of an amount of material flow. In a further arrangement, the equipment generates an output indicative of a thickness of the read marking material as applied to a surface.