Drawing Speed Research Articles

Investigations of Formability and Dynamic Recrystallization Development of Titanium Alloys During Dieless Wire Drawing Processes

This study investigates the formability and grain size evolution during the dieless wire drawing process of titanium alloy Ti–6Al–4V. First, thermocompression tests of Ti–6Al–4V billets are conducted to obtain their flow stresses at different temperatures and strain rates. Dynamic recrystallization (DRX)‐related constants and grain size prediction models for titanium alloy Ti–6Al–4V are established from the flow stress curves through regression analyses. Then, a finite element software DEFORM 2D coupled with the established DRX models is adopted for DRX volume fraction and grain size evolution simulations of titanium alloy Ti–6Al–4V during dieless wire drawing processes. The effects of various drawing conditions, such as drawing speed, drawing temperature, and area reduction, on the formability of the wire after the dieless drawing process are discussed. Finally, a dieless drawing machine with a high‐frequency induction heating apparatus and a cooling system is developed. A series of experiments of dieless drawing of titanium alloy Ti–6Al–4V wires at different drawing speeds, drawing temperatures, and cooling rates are conducted. The analytical forming limits of area reductions and grain sizes are compared with experimental values to validate the finite element analysis and DRX models.

Nano-Structured Ridged Micro-Filaments (≥100 µm Diameter) Produced Using a Single Step Strategy for Improved Bone Cell Adhesion and Proliferation in Textile Scaffolds.

Textile scaffolds that are either 2D or 3D with tunable shapes and pore sizes can be made through textile processing (weaving, knitting, braiding, nonwovens) using microfilaments. However, these filaments lack nano-topographical features to improve bone cell adhesion and proliferation. Moreover, the diameter of such filaments should be higher than that used for classical textiles (10–30 µm) to enable adhesion and the efficient spreading of the osteoblast cell (>30 µm diameter). We report, for the first time, the fabrication of biodegradable nanostructured cylindrical PLLA (poly-L-Lactic acid) microfilaments of diameters 100 µm and 230 µm, using a single step melt-spinning process for straightforward integration of nano-scale ridge-like structures oriented in the fiber length direction. Appropriate drawing speed and temperature used during the filament spinning allowed for the creation of instabilities giving rise to nanofibrillar ridges, as observed by AFM (Atomic Force Microscopy). These micro-filaments were hydrophobic, and had reduced crystallinity and mechanical strength, but could still be processed into 2D/3D textile scaffolds of various shapes. Biological tests carried out on the woven scaffolds made from these nano-structured micro filaments showed excellent human bone cell MG 63 adhesion and proliferation, better than on smooth 30 µm- diameter fibers. Elongated filopodia of the osteoblast, intimately anchored to the nano-structured filaments, was observed. The filaments also induced in vitro osteogenic expression, as shown by the expression of osteocalcin and bone sialoprotein after 21 days of culture. This work deals with the fabrication of a new generation of nano-structured micro-filament for use as scaffolds of different shapes suited for bone cell engineering.

Motor Signatures in Digitized Cognitive and Memory Tests Enhances Characterization of Parkinson's Disease.

Although interest in using wearable sensors to characterize movement disorders is growing, there is a lack of methodology for developing clinically interpretable biomarkers. Such digital biomarkers would provide a more objective diagnosis, capturing finer degrees of motor deficits, while retaining the information of traditional clinical tests. We aim at digitizing traditional tests of cognitive and memory performance to derive motor biometrics of pen-strokes and voice, thereby complementing clinical tests with objective criteria, while enhancing the overall characterization of Parkinson’s disease (PD). 35 participants including patients with PD, healthy young and age-matched controls performed a series of drawing and memory tasks, while their pen movement and voice were digitized. We examined the moment-to-moment variability of time series reflecting the pen speed and voice amplitude. The stochastic signatures of the fluctuations in pen drawing speed and voice amplitude of patients with PD show a higher signal-to-noise ratio compared to those of neurotypical controls. It appears that contact motions of the pen strokes on a tablet evoke sensory feedback for more immediate and predictable control in PD, while voice amplitude loses its neurotypical richness. We offer new standardized data types and analytics to discover the hidden motor aspects within the cognitive and memory clinical assays.

Stress superposition effect in ultrasonic drawing of titanium wires: An experimental study

Benefits of ultrasonic vibration have been identified in metal forming and other manufacturing processes, yet the underlying mechanism has not yet been fully understood. In this paper, influences of ultrasonic vibration on the titanium wire drawing process were investigated in terms of ultrasonic amplitude, drawing speed, and position of the die. Longitudinal vibrations were superimposed upon the die via a tailor-made ultrasonic vibrator, whose dynamic performances were predicted by finite element analysis (FEA) and examined utilizing specific instruments. A single-pass ultrasonic wire drawing platform was established to measure the forming forces under various drawing conditions, which were subsequently compared with numerical simulation results. Surface morphologies of the drawn wires were inspected by scanning electron microscope (SEM). Results show that both increased ultrasonic amplitude and lowered drawing speed contribute to decreasing the drawing forces, but the efficiency is furthered influenced by location of the die. At the half-wavelength position, a significant drawing force reduction of 66.8% (from 22.5 N to 7.45 N) was observed with the ultrasonic amplitude and drawing speed of 9μm and 100 mm/s, respectively. At the quarter-wavelength position, however, the corresponding percentage reduction is only 21%. The phenomenon could be explained by the elastic stretching oscillation of the wire based on the stress superposition hypothesis.

Research on Three-Dimensional Electronic Navigation Chart Hybrid Spatial Index Structure Based on Quadtree and R-Tree

The three-dimensional (3D) visualization of the electronic navigation chart (ENC) can reflect the marine environment and various marine features truly, accurately, and directly, to reduce misoperation during chart use and improve the convenience of using the chart. Due to a large amount of ENC data, complex data structure, and uneven distribution in 3D space, the construction and real-time rendering of 3D ENCs depend on the retrieval speed of 3D spatial data. Improving the spatial retrieval efficiency of 3D ENC data is helpful for the rapid rendering of a 3D scene. In this paper, based on the S-100 universal hydrological data model (S-100) and the 3D characteristics to classify the ENC features and create the 3D ENC data set, a hybrid spatial index structure is proposed based on quadtree and R-tree and ENC features data structure, using the smallest minimum bounding box (SMBB) and classification retrieval methods to optimize the spatial index structure. All the ENC features are rendered in a 3D marine scene. By analyzing the overlap of ENC features and testing the efficiency of spatial index structure, the results show that this method can effectively reduce the overlap rate of index nodes and improve the efficiency of data retrieval, realize the effective management of 3D ENC data, and improve the drawing speed of 3D ENCs.

Automated Analysis of Drawing Process to Estimate Global Cognition in Older Adults: Preliminary International Validation on the US and Japan Data Sets.

BackgroundWith the aging of populations worldwide, early detection of cognitive impairments has become a research and clinical priority, particularly to enable preventive intervention for dementia. Automated analysis of the drawing process has been studied as a promising means for lightweight, self-administered cognitive assessment. However, this approach has not been sufficiently tested for its applicability across populations.ObjectiveThe aim of this study was to evaluate the applicability of automated analysis of the drawing process for estimating global cognition in community-dwelling older adults across populations in different nations.MethodsWe collected drawing data with a digital tablet, along with Montreal Cognitive Assessment (MoCA) scores for assessment of global cognition, from 92 community-dwelling older adults in the United States and Japan. We automatically extracted 6 drawing features that characterize the drawing process in terms of the drawing speed, pauses between drawings, pen pressure, and pen inclinations. We then investigated the association between the drawing features and MoCA scores through correlation and machine learning–based regression analyses.ResultsWe found that, with low MoCA scores, there tended to be higher variability in the drawing speed, a higher pause:drawing duration ratio, and lower variability in the pen’s horizontal inclination in both the US and Japan data sets. A machine learning model that used drawing features to estimate MoCA scores demonstrated its capability to generalize from the US dataset to the Japan dataset (R2=0.35; permutation test, P<.001).ConclusionsThis study presents initial empirical evidence of the capability of automated analysis of the drawing process as an estimator of global cognition that is applicable across populations. Our results suggest that such automated analysis may enable the development of a practical tool for international use in self-administered, automated cognitive assessment.

High speed multi-stage drawing process of hot-dip galvanised steel wires

In this paper, unique tests into the production of galvanised steel wires in industrial conditions were presented. It was demonstrated that three phenomena occur during the wire-drawing process at high speeds: namely, zinc sticking to the surface of drawing drums, zinc coating grinding caused by a larger friction surface area between the tool and the material, combined with the detachment of the zinc coating in the calibrating part of the die until the wire breaks and the drawing process is interrupted. After drawing at high speeds (over 15 m/s), the wires were characterised by a thin coat. The research carried out in the study showed a significant influence of the speed and the drawing angle on the mechanical and technological properties as well as the residual stresses in hot-dip galvanised steel wires. Depending on the speed of drawing, wires drawn in dies with an angle α = 7°, in relation to wires drawn in dies with an angle α = 3°, were characterised by 7.8–12% higher yield strength, and 3.7–7.1% higher tensile strength, 16.7% and 21.5% lower elongation, 24.3% lower reduction in area, 33% lower number of twist and bends, and 145.9% higher residual stresses.

Formation of break-out induced by longitudinal crack of billet

Due to the characteristics of large shrinkage, peritectic steel is sensitive to longitudinal crack defects. Through the analysis of the breakout shell of a domestic factory, the mechanism of longitudinal crack breakout of peritectic steel is revealed. The following conclusions are obtained: the carbon content of the steel is 0.077%, which is in the peritectic range, but Mn / S = 128, and the ratio of manganese and sulfur is relatively high. Although P + S = 0.0263%, the longitudinal crack defect still occurs when the harmful elements are very low. When breakout occurs, the superheat is 35 °C, the drawing speed is 2.5m/min, which is one of the main causes of longitudinal crack. The longitudinal crack occurs about 200-600mm away from the mold bottom and on the center of the side. After the original shell is formed, intermittent unevenness occurs. This unevenness can sometimes be repaired, but sometimes can’t. Therefore, the longitudinal crack and break-out are easy to occur after the thinner blank shell leaves the mold.

Research on the control technology of Ds inclusion and Oxygen content in GCr15 bearing steel

This paper presents a method for controlling Ds inclusions and oxygen content in bearing steel produced by EAT-LF-VD-CCM process, including EAF initial refining process, LF external refining process, VD vacuum treatment process and continuous casting production process. By reasonably reducing the basicity of slag, adjusting the amount and sequence of alloy addition, the carbon content of EAF steel is appropriately increased and the temperature of steel extraction is reasonably selected. Optimize the amount of deoxidizer added in off~furnace refining, improve the basicity of refining slag, control the vacuum time, aluminum loss and stirring volume; In the continuous casting process, middle alkaline coating agent, constant drawing speed and protective pouring process are used to control and remove Ds inclusions in bearing steel. The bearing steel produced by this process can remove big sized Ds inclusions in the steel, while the total oxygen content is controlled below 7ppm.

Investigations on Effects of Forming Parameters on Product Dimensions in Cold Drawing of AISI-316 Stainless Steel Rods

Cold drawing is a commonly used metal forming technique carried out by pulling a billet through a die cavity to obtain desired dimensions. Ideally, the cross-sectional area of the drawn product should be equal to that of the die at its exit; however, the former one is always larger after drawing, in practice. In this study, cold drawing of an AISI-316 stainless steel rod is investigated through finite element analysis. The difference between the product radius and the die radius is denoted by ∆R. A series of simulations using combinations of various forming parameters, including semi-die angle, bearing ratio, reduction ratio, drawing speed and friction coefficient, are conducted to find out the dominant factors of ∆R. It is found that ∆R is mainly affected by semi-die angle, reduction ratio and friction. An empirical formula for ∆R, including various parameters, is established according to the simulation results and verified by drawing experiments as well. Using this empirical formula, the product dimensions can be predicted in advance and proper forming parameters can be chosen to decrease ∆R and improve the product quality.

Engineering of tenogenic patch scaffold with fibrous microtopography and reinforcement via uniaxial cold-drawing

Rotator cuff tendon repair remains a great challenge in orthopedic surgery. Attempts to inspire the microenvironmental recapitulation from in vivo have rarely elaborated on aligned and reinforced fibrous microtopography required for clinical application. Furthermore, compromises with fibrous densification during fabrication often limit the scaffold’s relevance in translational medicine. Here, we reported a facile and scalable method of uniaxial cold-drawing for engineering tendon patch scaffold. Comprised of bioactive and structure-supporting portions, the scaffold obtained featured microtopography of aligned and sparely-stacked fibres while providing mechanical properties approaching to that of human rotator cuff tendon. The structural integration between scaffold’s two portions resulted in stable and reliable fabrication, where parameters of drawing ratio, speed and temperature influenced the formation of fibrous microtopography. When mesenchymal stem cells were cultured with the scaffold, phenotypic markers of tenogenesis including scleraxis, decorin and tenomodulin were examined higher over nonfibrous controls. Our results further demonstrated that expression of collagen type I was associated with highly aligned intracellular cytoskeleton and the higher nucleus alignment and elongation, coupling with down-regulated cell proliferation and noncytotoxicity.

Basaltic Glass Fibers from Industrial Wastes: A Laboratory-Scale Technical Feasibility Study

This study demonstrated the physical–chemical and technical feasibility of recycling EAF slag granulated by rapid cooling with gas to produce continuous glass fibers with a basalt-like composition. To adjust the chemical composition, a silica fume-based secondary raw material was used, together with other additives. Different compositions were tested: 50% EAF slag and 50% silica fume (sample C1); 40% EAF slag, 50% silica fume and 10% Na2O (sample C2); 40% EAF slag, 50% silica fume, 5% Na2O and 5% K2O (sample C3); 20% EAF slag, 57% silica fume, 10% Na2O and 13% alkali earth oxides (sample C4); 26% EAF slag, 35% silica fume, 7% CaO and 12% Na2O (sample C5); 26% EAF slag, 35% silica fume, 4% CaO and 15% Na2O (sample C6). The last composition allowed obtaining fibers up to 5–6 m long, with a diameter between 60 and 180 µm. The process involved using a refractory material crucible with a calibrated bottom orifice as a single nozzle bushing. The optimal temperature range for fiber forming was between 1115 and 1125 °C, with a linear drawing speed of about 2 m/s. Preliminary mechanical tests were performed. Based on these results, potential further recycling applications of granulated EAF slag in the production of basalt-like glass for noncontinuous fiber production for mechanical reinforcement or for thermal–acoustic insulation can also be foreseen.

Tunable distributed sensing performance in Ca-based nanoparticle-doped optical fibers

Rayleigh scattering enhanced nanoparticle-doped optical fibers is a technology very promising for distributed sensing applications, however, it remains largely unexplored. This work demonstrates for the first time the possibility of tuning Rayleigh scattering and optical losses in Ca-based nanoparticle-doped silica optical fibers by controlling the kinetics of the re-nucleation process that nanoparticles undergo during fiber drawing by controlling preform feed, drawing speed and temperature. A 3D study by SEM, FIB-SEM and optical backscatter reflectometry (OBR) reveals an early-time kinetics at 1870 °C, with tunable Rayleigh scattering enhancement 43.2–47.4 dB, regarding a long-haul single mode fiber, SMF-28, and associated sensing lengths of 3–5.5 m. At 2065 °C, kinetics is slower and nanoparticle dissolution is favored. Consequently, enhanced scattering values of 24.9–26.9 dB/m and sensing lengths of 135–250 m are attained. Finally, thermal stability above 500 °C and tunable distributed temperature sensitivity are proved, from 18.6 pm/°C to 23.9 pm/°C, ∼1.9–2.4 times larger than in a SMF-28. These results show the promising future of Rayleigh scattering enhanced nanoparticle-doped optical fibers for distributed sensing.

Importance of Finite Element Analysis for Verification of Technological Parameters of Seamless Tubes Production Obtained by Experiment

Experimental research on the process of cold tubes drawing was performed in order to obtain important information about the behaviour of the tube material in the drawing tool during the drawing to the required outer diameter of Ø12 mm. The DEFORM-3D simulation software was an important tool for verifying the plastic flow of material in the drawing tool (i.e. drawing die), as well as for optimizing the technological parameters of cold tubes drawing. In the finite element (FE) analysis, emphasis was placed on determining the influence of tool geometry, strain degree, drawing speed and friction on the size of the drawing force and the quality of production of drawn tubes. The paper points out the importance of simulation software for common comparison of results obtained from laboratory experiment and FE analysis of the process of tubes drawing. By comparing the results, the reliability of the used simulation software was proved, as the results were identical for all monitored technological parameters. Computer simulation brings valuable knowledge that is important for the correct design of the drawing tool as well as for the technology of production of tubes with precise dimensions.

Statistical Modeling and Optimization of the Drawing Process of Bioderived Polylactide/Poly(dodecylene furanoate) Wet-Spun Fibers.

Drawing is a well-established method to improve the mechanical properties of wet-spun fibers, as it orients the polymer chains, increases the chain density, and homogenizes the microstructure. This work aims to investigate how drawing variables, such as the draw ratio, drawing speed, and temperature affect the elastic modulus (E) and the strain at break (εB) of biobased wet-spun fibers constituted by neat polylactic acid (PLA) and a PLA/poly(dodecamethylene 2,5-furandicarboxylate) (PDoF) (80/20 wt/wt) blend. Drawing experiments were conducted with a design of experiment (DOE) approach following a 24 full factorial design. The results of the quasi-static tensile tests on the drawn fibers, analyzed by the analysis of variance (ANOVA) and modeled through the response surface methodology (RSM), highlight that the presence of PDoF significantly lowers E, which instead is maximized if the temperature and draw ratio are both low. On the other hand, εB is enhanced when the drawing is performed at a high temperature. Finally, a genetic algorithm was implemented to find the optimal combination of drawing parameters that maximize both E and εB. The resulting Pareto curve highlights that the temperature influences the mechanical results only for neat PLA fibers, as the stiffness increases by drawing at lower temperatures, while optimal Pareto points for PLA/PDoF fibers are mainly determined by the draw ratio and the draw rate.

Low-Cost 3D Printer Drawn Optical Microfibers for Smartphone Colorimetric Detection.

A fused deposition modeling (FDM) 3D printer extruder was utilized as a micro-furnace draw tower for the direct fabrication of low-cost optical fibers. An air-clad multimode microfiber was drawn from optically transparent polyethylene terephthalate glycol (PETG) filament. A custom-made spooling collection allows for an automatic variation of fiber diameter between ϕ ∼ 72 to 397 μm by tuning the drawing speed. Microstructure imaging as well as the 3D beam profiling of the transmitted beam in the orthogonal axes was used to show good quality, functioning microfiber fabrication with uniform diameter and identical beam profiles for orthogonal axes. The drawn microfiber was used to demonstrate budget smartphone colorimetric-based absorption measurement to detect the degree of adulteration of olive oils with soybean oil.

Investigating the Effect of Drawing Process Parameters on Borosilicate Glass Fiber Thickness

Borosilicate glasses have many usage areas due to high thermal and chemical resistance with a very low thermal expansion coefficient. The number of waste borosilicate glasses is increasing in direct proportion to their usage areas. Creating new usage areas by recycling these glasses will provide cost savings. In this paper, the fiber drawing method is used to recycle borosilicate glass. The aim of this article is to investigate the effect of winding speed and temperature of drawing process on fiber thickness. The fiber drawing process was performed at specific temperatures (1100 °C, 1200 °C, and 1300 °C) and at specific winding speeds (50 rpm, 175 rpm, and 300 rpm). In this context, the thermal behavior of borosilicate glasses was determined by DSC and TGA analysis. The structural, elemental, and chemical corrosion resistance properties of borosilicate glass fibers were examined by SEM, XPS, and corrosion test, respectively. The results show that the fiber thickness increased with the increase in the amount of material fed in the crucible, while it decreased with the increase of fiber drawing speed and time.

Speed and space: Rates of motion in health and wellbeing

The posthumanist turn in health and wellbeing research has paid attention to the qualities of space, particularly through the work of geographers. Although a range of these qualities have been explicitly articulated and well explored, a clear omission in the literature has been ‘speed’ - an important quality in its own right, and evident in all other qualities. This review paper takes a good look at speed. First it considers what speed is, and the myriad ways in which it arises and is registered according to science and other intellectual paradigms. Second it considers speed as a distinctive feature of twenty-first century life and the health and wellbeing involvements and implications of this life. Third it considers some partial precedent for a focus on speed and space in health and wellbeing research, by drawing speed out of current studies where it is implicit or a minor consideration. To conclude, the paper thinks about the issues, challenges and possibilities for researching speed more fully, and the opportunities this might open up.

Design and Implementation of Automatic Drawing System for Geological Section

The geological section map uses the specified geological elements to express the characteristics and attributes of the geological body at a certain depth below the section line. By analyzing the functional requirements of the automatic geological section drawing system, the structure and functional modules of the system are designed in detail. The system was developed with AutoCAD as the platform and C# as the development language with the help of CAD secondary development technology. Taking the geological section of Xishimen iron ore mine as an example, the system proved to be efficient in drawing the section, and significantly improved the speed and quality of the section drawing.

A novel superplastic dieless drawing using fracture phenomenon for fabrication of metal tubular microneedles

A new dieless drawing using fracture phenomenon is proposed to fabricate superplastic microneedles with ultrafine tip diameter. The fracture type of high ductility after superplastic deformation is used for fabrication of ultrafine tip. The tapered shape of the microneedles is controlled by varying the drawing speed. Shape control was realized using a fixed water-cooling coil for a needle length below 70 mm. Heating temperature and drawing acceleration affect the tip outer diameter. The microneedle with a tip outer diameter of about 50 μm is fabricated under optimized drawing conditions. The fabricated microneedles can be used for medical and biotechnology applications.