scholarly journals Development of Rolling Technology for an Iron-Based Shape-Memory-Alloy

2016 ◽  
Vol 854 ◽  
pp. 79-86 ◽  
Author(s):  
Christian Leinenbach ◽  
Christoph Czaderski ◽  
Julien Michels ◽  
Marcel Graf ◽  
Rudolf Kawalla

Low cost Fe-Mn-Si based shape memory alloys (SMA) have drawn much attention during the last two decades as a cost-effective alternative to the expensive Ni-Ti based SMA. In particular, the alloy Fe-17Mn-5Si-10Cr-4Ni-1(V,C) (mass%), which has been developed at Empa shows very promising properties with regard to potential commercial applications in civil and mechanical engineering. This alloy has a higher reverse transformation temperature and larger thermal hysteresis in comparison to the Ni-Ti based alloys, which is adequate for producing stable recovery stresses at room temperature. Furthermore, recovery stresses of up to 300 MPa after heating to only 160°C can be achieved without so-called ‘training’ treatment. Furthermore, the alloy can be easily and cost effectively produced under standard air melting and casting conditions. For availability of these heavily microstructure dependent skills for civil and mechanical engineering, e.g. as prestressing elements in concrete structures or coupling/clamping devices, a process chain for manufacturing is necessary. Therefore, a hot and cold rolling technology for strip production with thermal heat treatment processes was developed at TU Bergakademie on base of experimental simulation results. The last one helps to understand the dependencies of deformation parameters, the deformation behavior and their influence to the microstructure evolution in correlation to the recovery.This paper discusses the basic material properties, recovery stress formation behavior and finally the feasibility of the alloy as reinforcing elements in civil engineering applications by using a rolling technology for flat products.

2007 ◽  
Vol 539-543 ◽  
pp. 763-768 ◽  
Author(s):  
M. García de Cortázar ◽  
Javier Goñi ◽  
J. Coleto ◽  
I. Agote ◽  
P. Egizabal ◽  
...  

A new cost effective process to produce discontinuously reinforced (TiB) TMCs has been developed. The article presents general features of the composites, microstructural characteristics and mechanical properties. The production and characterization of two potential commercial applications are also discussed.


Ingeniería ◽  
2018 ◽  
Vol 23 (1) ◽  
pp. 70 ◽  
Author(s):  
Edwin Blasnilo Rua Ramirez ◽  
Fernando Jimenez Diaz ◽  
German Andres Gutierrez Arias ◽  
Nelson Iván Villamizar

Context: 3D printing can be used for a wide range of tasks such as the design and testing of prototypes and finished products in a shorter time. In mechanical engineering, prototype designs are continuously generated in academic class activities and final coursework projects by students and teachers. However, students show limitations while understanding the abstract concepts represented with such designs.Method: Firstly, a large scale 3D printer with improved technical specifications compared to traditional market options and similar price, was fabricated. By means of free software and hardware tools and easy-to-obtain alternative manufacturing materials, it was possible to decrease its manufacturing and operating costs. Then a set of study cases utilising the 3D printer in three different subject classes were designed and tested with two cohorts of students of Mechanical Engineering programme.Results: It was feasible to fabricate a cost-effective and practical 3D printer for constructing prototypes and pieces that benefit teaching and learning concepts in engineering and design areas. The experiments carried out in three subjects of engineering courses with second-year students, showed a similar trend of improving the average course grades, as it was observed in two cohorts in different terms.Conclusions: This type of low cost 3D printer obtained academic advantages as a didactic tool for the learning process in engineering and design subjects. Future work will consider applying this tool to other courses and subjects to further evaluate its convenience and effectivity.


2013 ◽  
Vol 135 (2) ◽  
Author(s):  
Sandeep Chaturvedi ◽  
Shiban K. Koul

Design, fabrication, and test results of a novel 3-layer RF package using a commonly available high frequency laminate are presented in this paper. The developed package can be manufactured using standard multilayer printed circuit board (PCB) manufacturing techniques making it cost effective for commercial applications. The package exhibits excellent RF characteristics up to 6 GHz.


2007 ◽  
Vol 539-543 ◽  
pp. 1827-1832 ◽  
Author(s):  
Markus Hirschmann ◽  
Carolin Körner ◽  
Robert F. Singer

Integral foam molding (IFM) is an economical near net-shape technology to produce monolithic castings with solid skin, foamed core and continuous density transition between skin and core. It was developed for polymers in the 1960s. But it took about ten years to optimize the molding technique and the quality of the polymer integral foam parts to a marketable stage. Meanwhile, polymer integral foam parts are established in a lot of commercial applications. The situation is completely different for metals. The first attempts to produce metal integral foam parts were made only a few years ago. A cost effective injection molding technique for magnesium integral foam was developed at the WTM-Institute in Erlangen, Germany. The low-cost production in combination with the integral foam properties low density, high weight specific bending stiffness and remarkable damping capacity is very promising. At the beginning we produced only parts with simple shape, for example plates. But if we think about commercial applications, more complex parts with a three-dimensional shape are required. The focus of this paper is on new developments concerning the production of magnesium integral foam parts with complex shape like a casing cover or a door handle.


Materials ◽  
2013 ◽  
Vol 6 (12) ◽  
pp. 5447-5465 ◽  
Author(s):  
Andrés Lantada ◽  
María Rebollo

2017 ◽  
Author(s):  
DW Mohr ◽  
A Naguib ◽  
NI Weisenfeld ◽  
V Kumar ◽  
P Shah ◽  
...  

AbstractCurrent short-read methods have come to dominate genome sequencing because they are cost-effective, rapid, and accurate. However, short reads are most applicable when data can be aligned to a known reference. Two new methods for de novo assembly are linked-reads and restriction-site labeled optical maps. We combined commercial applications of these technologies for genome assembly of an endangered mammal, the Hawaiian Monk seal.We show that the linked-reads produced with 10X Genomics Chromium chemistry and assembled with Supernova v1.1 software produced scaffolds with an N50 of 22.23 Mbp with the longest individual scaffold of 84.06 Mbp. When combined with Bionano Genomics optical maps using Bionano RefAligner, the scaffold N50 increased to 29.65 Mbp for a total of 170 hybrid scaffolds, the longest of which was 84.78 Mbp. These results were 161X and 215X, respectively, improved over DISCOVAR de novo assemblies. The quality of the scaffolds was assessed using conserved synteny analysis of both the DNA sequence and predicted seal proteins relative to the genomes of humans and other species. We found large blocks of conserved synteny suggesting that the hybrid scaffolds were high quality. An inversion in one scaffold complementary to human chromosome 6 was found and confirmed by optical maps.The complementarity of linked-reads and optical maps is likely to make the production of high quality genomes more routine and economical and, by doing so, significantly improve our understanding of comparative genome biology.


Author(s):  
Tanwi Singh ◽  
Anshuman Sinha

The major risk associated with low platelet count in pregnancy is the increased risk of bleeding during the childbirth or post that. There is an increased blood supply to the uterus during pregnancy and the surgical procedure requires cutting of major blood vessels. Women with thrombocytopenia are at increased risk of losing excessive blood. The risk is more in case of caesarean delivery as compared to vaginal delivery. Hence based on above findings the present study was planned for Assessment of the Platelet Count in the Pregnant Women in IGIMS, Patna, Bihar. The present study was planned in Department of Pathology, Indira Gandhi Institute of Medical Science, Patna, Bihar, India. The present study was planned from duration of January 2019 to June 2019. In the present study 200 pregnant females samples received for the platelet estimation were enrolled in the present study. Clinically platelet indices can be a useful screening test for early identification of preeclampsia and eclampsia. Also platelet indices can assess the prognosis of this disease in pregnant women and can be used as an effective prognostic marker because it correlates with severity of the disease. Platelet count is a simple, low cost, and rapid routine screening test. Hence the data generated from the present study concludes that platelet count can be used as a simple and cost effective tool to monitor the progression of preeclampsia, thereby preventing complications to develop during the gestational period. Keywords: Platelet Count, Pregnant Women, IGIMS, Patna, Bihar, etc.


2019 ◽  
Vol 2019 (4) ◽  
pp. 7-22
Author(s):  
Georges Bridel ◽  
Zdobyslaw Goraj ◽  
Lukasz Kiszkowiak ◽  
Jean-Georges Brévot ◽  
Jean-Pierre Devaux ◽  
...  

Abstract Advanced jet training still relies on old concepts and solutions that are no longer efficient when considering the current and forthcoming changes in air combat. The cost of those old solutions to develop and maintain combat pilot skills are important, adding even more constraints to the training limitations. The requirement of having a trainer aircraft able to perform also light combat aircraft operational mission is adding unnecessary complexity and cost without any real operational advantages to air combat mission training. Thanks to emerging technologies, the JANUS project will study the feasibility of a brand-new concept of agile manoeuvrable training aircraft and an integrated training system, able to provide a live, virtual and constructive environment. The JANUS concept is based on a lightweight, low-cost, high energy aircraft associated to a ground based Integrated Training System providing simulated and emulated signals, simulated and real opponents, combined with real-time feedback on pilot’s physiological characteristics: traditionally embedded sensors are replaced with emulated signals, simulated opponents are proposed to the pilot, enabling out of sight engagement. JANUS is also providing new cost effective and more realistic solutions for “Red air aircraft” missions, organised in so-called “Aggressor Squadrons”.


2018 ◽  
Vol 32 (2) ◽  
pp. 103-119
Author(s):  
Colleen M. Boland ◽  
Chris E. Hogan ◽  
Marilyn F. Johnson

SYNOPSIS Mandatory existence disclosure rules require an organization to disclose a policy's existence, but not its content. We examine policy adoption frequencies in the year immediately after the IRS required mandatory existence disclosure by nonprofits of various governance policies. We also examine adoption frequencies in the year of the subsequent change from mandatory existence disclosure to a disclose-and-explain regime that required supplemental disclosures about the content and implementation of conflict of interest policies. Our results suggest that in areas where there is unclear regulatory authority, mandatory existence disclosure is an effective and low cost regulatory device for encouraging the adoption of policies desired by regulators, provided those policies are cost-effective for regulated firms to implement. In addition, we find that disclose-and-explain regulatory regimes provide stronger incentives for policy adoption than do mandatory existence disclosure regimes and also discourage “check the box” behavior. Future research should examine the impact of mandatory existence disclosure rules in the year that the regulation is implemented. Data Availability: Data are available from sources cited in the text.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Robert Christie

Abstract This paper presents an overview of the general chemical principles underlying the structures, synthesis and technical performance of azo pigments, the dominant chemical class of industrial organic pigments in the yellow, orange, and red shade areas, both numerically and in terms of tonnage manufactured. A description of the most significant historical features in this group of pigments is provided, starting from the discovery of the chemistry on which azo colorants are based by Griess in the mid-nineteenth century, through the commercial introduction of the most important classical azo pigments in the early twentieth century, including products known as the Hansa Yellows, β-naphthol reds, including metal salt pigments, and the diarylide yellows and oranges, to the development in the 1950s and 1960s of two classes of azo pigments that exhibit high performance, disazo condensation pigments and benzimidazolone-based azo pigments. A feature that complicates the description of the chemical structures of azo pigments is that they exist in the solid state as the ketohydrazone rather than the hydroxyazo form, in which they have been traditionally been illustrated. Numerous structural studies conducted over the years on an extensive range of azo pigments have demonstrated this feature. In this text, they are referred to throughout as azo (hydrazone) pigments. Since a common synthetic procedure is used in the manufacture of virtually all azo (hydrazone) pigments, this is discussed in some detail, including practical aspects. The procedure brings together two organic components as the fundamental starting materials, a diazo component and a coupling component. An important reason for the dominance of azo (hydrazone) pigments is that they are highly cost-effective. The syntheses generally involve low cost, commodity organic starting materials and are carried out in water as the reaction solvent, which offers obvious economic and environmental advantages. The versatility of the approach means that an immense number of products may be prepared, so that they have been adapted structurally to meet the requirements of many applications. On an industrial scale, the processes are straightforward, making use of simple, multi-purpose chemical plant. Azo pigments may be produced in virtually quantitative yields and the processes are carried out at or below ambient temperatures, thus presenting low energy requirements. Finally, provided that careful control of the reaction conditions is maintained, azo pigments may be prepared directly by an aqueous precipitation process that can optimise physical form, with control of particle size distribution, crystalline structure, and surface character. The applications of azo pigments are outlined, with more detail reserved for subsequent papers on individual products.


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