Material flow

About: Material flow is a research topic. Over the lifetime, 3050 publications have been published within this topic receiving 36844 citations. The topic is also known as: material stream.

Microstructure and texture correlation of secondary heating assisted dissimilar friction stir welds of aluminum alloys

Abstract: Present work aims to study the influence of secondary heating on material behavior during the friction stir welding (FSW) and examine it through the texture analysis. In the present context, the secondary heating pertains to the additional heat provided using a gas torch other than the heat primarily produced due to the process itself. Stop tool action technique is used to appraise the material flow around the pin. The material flow and evolution of textures during the process is studied by employing electron backscatter diffraction analysis. For analysis, the transverse sections of dissimilar FSW joints of AA6061-AA7075 and AA7075-AA2014 prepared with and without the application of secondary heating keeping the tool pin embedded in the joint are used. The basic assertions on strain rate based upon texture analysis and grain boundary engineering are used to explain the nature of material behavior during the process. The misorientation angle distribution is observed to shift towards random distribution for severe plastic deformation and additional heat supplied. Texture analysis reveals dominance of B / B ‾ shear texture with sufficient C component in joints supplied with additional heating. For AA7075-AA2014 (without secondary heating) strong α-fiber is observed in the texture orientation distribution function plots. An equation is established to estimate the material volume flow around the pin in one revolution. The optical micrographs of welded joints prepared with and without use of secondary heating are compared to visualize the increase in material flow volume. The hardness of the joints obtained tend to decrease along the weld section on application of additional heat due to the dissolution of precipitates.

Analysing material and embodied environmental flows of an Australian university — Towards a more circular economy

Abstract: Humans are extracting and consuming unprecedented quantities of materials from the crust of the Earth. Contributing to this consumption, university campuses require large amounts of materials to operate. This offers opportunities for the implementation of circular economy principles that optimise material use and demonstrate best practice to future generations of decision makers, globally. This paper uses the Parkville campus of the University of Melbourne as a single revelatory case study to quantify its material flow for 2017. We use extremely disaggregated procurement data of 11 555 purchases of materials, mapped against 189 different material archetypes to estimate material inflows. Material outflows are sourced directly from the waste management contractor of the University. We also quantify the embodied energy, water, and greenhouse gas emissions of all inflows, using environmentally extended input-output analysis. Results show that procurement-related inflows tend to represent a small share (∼4%) of the total material flows (2 280 Gg), but result in significant environmental effects due to the nature of the materials (e.g. electronics, cabling, photovoltaic panels, furniture, etc.). The modelled procurement-related purchases result in 22 587 GJ of energy, 1 477 GgCO2e of greenhouse gas emissions and 30 891 kL of water, and 3.46 MAUD in cost, annually. Yet, the majority of material flows on campus tend to be generated by non-procurement-related drivers, notably food and food packaging waste resulting from retail on and off campus. Based on these findings, the paper recommends a series of actions that universities and large organisations can adopt to transition to a more circular economy.

STREAMS: a new method for analysing material flows through society

Abstract: For the development of material, product and waste oriented policies, knowledge about the flow, use and disposal of materials through society is necessary. The risks of taking policy measures leading to suboptimum solutions of environmental problems call for an integral survey of material flows through society. However, up to now, integral analyses of physical material flows have been lacking. Problems such as differences in definitions, in subdivisions of flows and in reference years make it difficult to relate data from different sources to obtain an overall view. In this article, STREAMS, a new method to calculate physical material flows through society, is proposed. The method is based on the so-called supply and use tables, which describe a country’s economy in terms of supply and use of materials, products and services by industries, service sectors and consumers. In our approach, materials and products are tracked on their way from extraction of raw materials to the final consumption of products and beyond, into the stage of waste. The method has the advantage of deriving almost all data from one source. In this article the method is described. In a separate study, the method is applied to obtain an integral survey of the flow of plastics through The Netherlands, showing that the method can be used to assess the final materials consumption on a highly detailed level.

Optimal concentrations in transport systems.

Abstract: Many biological and man-made systems rely on transport systems for the distribution of material, for example matter and energy. Material transfer in these systems is determined by the flow rate and the concentration of material. While the most concentrated solutions offer the greatest potential in terms of material transfer, impedance typically increases with concentration, thus making them the most difficult to transport. We develop a general framework for describing systems for which impedance increases with concentration, and consider material flow in four different natural systems: blood flow in vertebrates, sugar transport in vascular plants and two modes of nectar drinking in birds and insects. The model provides a simple method for determining the optimum concentration copt in these systems. The model further suggests that the impedance at the optimum concentration μopt may be expressed in terms of the impedance of the pure (c = 0) carrier medium μ0 as μopt 2(α)μ0, where the power α is prescribed by the specific flow constraints, for example constant pressure for blood flow (α = 1) or constant work rate for certain nectar-drinking insects (α = 6). Comparing the model predictions with experimental data from more than 100 animal and plant species, we find that the simple model rationalizes the observed concentrations and impedances. The model provides a universal framework for studying flows impeded by concentration, and yields insight into optimization in engineered systems, such as traffic flow.

Correcting the stress-strain curve in hot compression test using finite element analysis and taguchi method

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..