Metal composite parts are widely used in different industries owing to their significant improvement in material properties, such as mechanical strength, electrical conductivity, and corrosion ...resistivity, compared to traditional single metals. Such composite parts can be manufactured and processed in different ways to achieve the desired geometry and quality. Among various metal forming techniques, drawing is the most commonly used process to produce long composite wires or rods from raw single materials. During the drawing process of composite wires or rods, not only does the core radius ratio change, but the core or sleeve layer may also undergo necking or fracture due to excessive tensile stresses in the softer layer. In this paper, bimetallic rods with AISI-1006 low-carbon steel cores and C10100 oxygen-free electronic copper sleeves are modeled using the finite element software DEFORM. The simulation models are verified by drawing experiments. The effects of initial bonding conditions, the initial core ratio, reduction ratio, semi-die angle, drawing speed, and friction on the plastic deformation behavior of the bimetallic rods are investigated. The results indicate that the initial bonding conditions have a great impact on the deformation behavior of the billets in terms of strain distribution, material flow, residual stress, and the final core ratio. The permissible forming parameters for obtaining a sound product are investigated as well. With the aid of these analyses, the drawing process and the quality of the products can be controlled steadily.
This book examines the application of drawing in the design process of classical architecture, exploring how the tools and techniques of drawing developed for architecture subsequently shaped ...theories of vision and representations of the universe in science and philosophy. Building on recent scholarship that examines and reconstructs the design process of classical architecture, John R. Senseney focuses on technical drawing in the building trade as a model for the expression of visual order, showing that the techniques of ancient Greek drawing actively determined concepts about the world. He argues that the uniquely Greek innovations of graphic construction determined principles that shaped the massing, special qualities and refinements of buildings and the manner in which order itself was envisioned.
A significant increase in roughness of dieless-drawn wires due to the strain-induced roughness phenomenon has been documented. For small-diameter wires, even a slight surface relief creates stress ...concentrations that may contribute to the wire breakage during cold drawing. This, in turn, significantly limits the achievable diameter of the product and the efficiency of drawing process. The present study, however, demonstrates that reducing the wire roughness is possible by combining the dieless and conventional drawing methods. Thus, it is possible to improve the process workability threefold when compared to dieless drawing alone, and the product quality is simultaneously improved. In addition, the surface defects typical to the dieless-drawn wires have been significantly reduced, resulting in an increase in the wire strength. This new combined technology enables a significant reduction in the wire diameter and facilitates an economical large-scale production of ultra-thin wires. In addition, based on the classic drawing and dieless drawing process, a brass wire with a diameter of 0.017 mm has been manufactured. Six times thinner than a human hair, it is believed to be the thinnest long brass wire currently manufactured in the world.
Steel tire cord and steel saw wire represent typical precision pearlitic steel wire rods of wire products; it is a very important solar energy material with a diameter about 50 μm. This paper mainly ...discusses the research progress of the wire rod drawing process, and its main contents are as follows: First section—the control of the wire rod surface quality is summarized, including the thickness of the surface decarburization layer, the phase composition and thickness of the surface iron oxide scale, and the removal of surface iron oxide scale. Then, the research progress of the wire rod water bath treatment process during sorbitization is summarized. In addition, the development of brass plating technology for steel wire is summarized, including copper plating technology, coating phase composition, etc. Furthermore, the development of steel wire drawing methods is summarized. Finally, the development of the dies used in steel wire drawings is summarized.
Learning by drawing can be an effective strategy for supporting science text comprehension. However, drawing can also be cognitively demanding and time consuming, and students may not create quality ...drawings without sufficient guidance. Furthermore, evidence for drawing is often based on comparisons to weak control conditions, such as students who only read the text without provided illustrations. In this review, we synthesize past research to help draw boundary conditions for learning by drawing, focusing on the role of comparison conditions and drawing guidance. First, we analyze how drawing compares to each of four control conditions: reading only, text-focused strategies (e.g., summarizing), other model-focused strategies (e.g., imagining), or viewing instructor-provided illustrations. Next, we distinguish among four levels of drawing guidance: minimal guidance, drawing training, partially provided illustrations, and comparison to instructor-provided illustrations. Our findings indicate that when compared to only reading the text or using text-focused strategies, creating drawings is consistently more effective at fostering comprehension and transfer, regardless of the level of drawing guidance provided. However, when compared to other model-focused strategies or to viewing instructor-provided illustrations, effects of creating drawings are mixed and may depend on the level of drawing guidance provided, among other factors. We discuss the theoretical and practical considerations of our findings and suggest several directions for broadening research on drawing.
A tripartite‐circle drawing of a tripartite graph is a drawing in the plane, where each part of a vertex partition is placed on one of three disjoint circles, and the edges do not cross the circles. ...We present upper and lower bounds on the minimum number of crossings in tripartite‐circle drawings of
K
m
,
n
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p and the exact value for
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2
,
2
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n. In contrast to 1‐ and 2‐circle drawings, which may attain the Harary–Hill bound, our results imply that balanced restricted 3‐circle drawings of the complete graph are not optimal.
In order to reduce the weight and energy of vehicles, the steel sheets used in automotive manufacturing must be made of materials with a thinner material thickness and higher strength both to reduce ...the weight and save energy. For this reason, the use of high-tensile steel sheets is increasing. However, the drawing process in these cases is challenging due to the characteristics of high-tensile steel sheets. In order to solve this problem, a dome-shaped drawing die was manufactured and the tensile displacement characteristics of the material were studied using a high-tensile steel plate (SGAFC980). During the drawing process, the experiment involved changing the drawing speed, the pressure of the blank holder, and the size of the blank, which are the key factors. The results showed that when the drawing speed was slow, the inflow of the material was smooth, and the occurrence of cracks could be minimized. Pressure on the blank holder facilitates the inflow of the material and when set appropriately low, it does not cause wrinkles. As the size of the blank decreases, the clamping force applied by the blank holder decreases, and less tensile displacement of the material occurs. After the drawing process, changes in the materials were analyzed with an electron microscope, and the displacement characteristics of each location used in the experiment were considered.
Abstract
A novel method of cold drawing process of high spiral angle tube made of 304 stainless steel is proposed. Forming principles of high spiral angle tube are calculated. New drawing dies are ...designed and manufactured. Numerical simulation and corresponding experiments are carried out. Forming quality and defects of cold drawing are discussed. Various factors affecting metal flow during cold drawing process are studied in detail. Finite element model of cold drawing process is established. The variation of drawing load is presented. The distributions of equivalent stress and equivalent strain in different directions during cold drawing process are analyzed. Displacements of points in axial direction and circumference direction during cold drawing process are compared respectively. The evolutions of microstructure during cold drawing process are studied.
This meta-analysis, spanning 5 decades of Draw-A-Scientist studies, examined U.S. children's gender-science stereotypes linking science with men. These stereotypes should have weakened over time ...because women's representation in science has risen substantially in the United States, and mass media increasingly depict female scientists. Based on 78 studies (N = 20,860; grades K-12), children's drawings of scientists depicted female scientists more often in later decades, but less often among older children. Children's depictions of scientists therefore have become more gender diverse over time, but children still associate science with men as they grow older. These results may reflect that children observe more male than female scientists in their environments, even though women's representation in science has increased over time.
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