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1
Pantoja, Ayala Hector Hugo. "Improving the thermal performance of a light-weight metal roof in hot climates cHector Hugo Pantoja Ayala". Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61986.
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Carballo, Manuel. "Strength of z-purlin supported standing seam roof systems under gravity loading". Thesis, Virginia Tech, 1989. http://hdl.handle.net/10919/45952.
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The objective of the Standing Seam Roof Systems Research Project at the Virginia Polytechnic Institute and State University is to develop a design procedure for the strength of Z-purlin supported standing seam roof systems under gravity leading. Various approaches were taken to calculate the strength of systems with either torsional restraint, third point span restraint, or midspan restraint. Since few test results are available for single and three span continuous, two purlin line systems, the primary focus of this research is analytical. Even though the test setup used for these tests does not represent actual field conditions, the data obtained will be extremely useful in the development of analytical models to predict system strength. However, at least four multiple purlin line tests will be required to verify the accuracy of the design procedure. The analytical formulation will include the effects of sliding friction in the clips and "drape" restraint effects of the standing seam deck.
Master of Science
3
Tang, Louis. "Local failures of steel cladding systems under wind uplift". Thesis, Queensland University of Technology, 1997. https://eprints.qut.edu.au/36042/1/36042_Tang_1997.pdf.
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The profiled steel roof and wall cladding systems in Australia are commonly
made of very thin high tensile steels, and are fastened with screw fasteners at
their crests. In contrast, the steel cladding systems in the USA and Europe are
made of thicker mild steels, and are valley-fixed. Furthermore, the design of
cladding systems in Australia is governed by wind uplift/suction loading
whereas gravity load governs the USA/Europe cladding systems.
Since Australian Standards such as AS 1562-1990 (Design and Installation of
Roof and Wall Claddings) do not provide suitable design formulae for crestfixed
steel roof and wall cladding systems that are commonly used in Australia,
the design of steel cladding systems is at present based on laboratory testing.
The adoption of the American/European design specifications in the new edition
of Cold-formed Steel Structures AS4600-1996, is questionable with regard to its
__ sy.itability and applicability to the crest-fixed Australian steel cladding systems.
On the other hand, the current practice of testing individual steel roof and wall
products is inadequate and inefficient. Therefore, there is a need for specific
research and investigation on crest-fixed steel cladding systems under conditions
unique to Australia and its neighbouring countries.
This research project was aimed at improving the understanding of the behaviour
of crest-fixed steel cladding systems under wind uplift/suction loading, in
particular, the local failures in steel roof and wall cladding systems, and to
develop appropriate design formulae for the Australian building industry without
the need for individual cladding testing.
To achieve these objectives, a detailed experimental study using both two-span
cladding systems and suitable small scale sheeting models, and finite element
analyses were used. The two most important local failures observed in the steel cladding systems, the pull-out failure, and local dimpling and/or pullthrough/
pull-over failure, were investigated and appropriate design formulae
have been developed.
The splitting phenomenon observed with the pull-through/pull-over failure could
not be modelled adequately by the available finite element programs without a
suitable failure criterion. Hence, the design formulae developed here for pullthrough/
pull-over failure have some limitations, but avenues for further research
have been identified and discussed in this thesis.
4
Ho, Ho-chuen Federick. "Ferrous metal balance of Hong Kong : consumption, waste generation, recycling and disposal /". Hong Kong : University of Hong Kong, 1997. http://sunzi.lib.hku.hk/hkuto/record.jsp?B18734893.
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Ahmad, J. "Dephosphorisation of molten iron and steel". Thesis, Brunel University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379756.
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Yin, Maggie Huaying Materials Science & Engineering Faculty of Science UNSW. "Metal dusting of iron and low alloy steel". Awarded by:University of New South Wales. School of Materials Science and Engineering, 2006. http://handle.unsw.edu.au/1959.4/25188.
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Metal dusting is a kind of catastrophic corrosion phenomenon that can be observed in several of petrochemical processes. It occurs on iron-, nickel- and cobalt-base metals in carbonaceous atmospheres at high temperature when gaseous carbon activity is higher than one. The process is particularly rapid for ferritic alloys The aim of this project was to compare the dusting kinetics of pure iron and a 2.25Cr-1Mo alloy steel under CO-H2-H2O atmosphere at 650??C. Polished (3??m) samples of iron and the steel were exposed to flowing CO-H2-H2O gas atmospheres at 650??C, when the gases were supersaturated with respect to graphite. The partial pressure of CO was varied between 0.25 and 0.9 atm, and the carbon activity was varied from 2.35 to 16, in order to obtain a series of experimental conditions. In most experiments, pO2 was less than 7.37E-24 atm, and no iron oxide could form. However, Cr2O3 would always have been stable. When exposed to these gases, both iron and steel developed a surface scale of Fe3C which was buried beneath a deposit of carbon, containing iron-rich nanoparticles (the dust). Examination by Scanning Electron Microscopy allowed the observation of fine and coarse carbon nanotubes, and also spiral filaments. However, the morphology of the graphitic carbon was not sensitive to pCO and aC. Moreover, the carbon deposit was gas permeable, allowing continuing gas access to the underlying metal. At a fixed=4.5, the carburizing rate clearly increased with CO content from 0.25 to 0.68 atm. However, increasing the CO content to higher value led to decreased rates, indicating that carburizing rate reaches a maximum value at pCO=0.68 atm. When pCO was fixed at 0.25 atm and 0.68 atm, and carbon activity was varied. The induction period was extended by the formation of protective oxide layers at low values of carbon activity (aC= 2.35 and 2.55) where pO2 exceed the iron oxide formation value. For other reaction conditions, the carbon uptake rate for iron and steel did not increase with aC. The present work showed that the carbon deposition rates were not proportional to pCO or pCOpH2. Instead, the rate was affected by the partial pressure of all three reaction gases, and the carbon uptake rate for both materials could be expressed at r=k1pCOpH2+k2pCO2+k3pH22 and the rate constant k3 has a negative value, corresponding to coke gasification. From XRD analyses, it was found that cementite was the only iron-containing phase in the dusting product. The cementite particles acted as catalysts for carbon deposition from the gas. The same deposition process at the surface of the cementite layer led to its disintegration, thereby producing the particles. This disintegration process was faster on the steel than on pure iron. Consequently, the rates of both metal wastage and coke accumulation were faster for the steel. It is concluded that chromium and molybdenum do not stabilize the carbide but accelerate its disintegration process. It is suggested that Cr2O3 fine particles in the cementite layers provide more nucleation sites in the cementite layer on steel, explaining its more rapid dusting kinetics. However, appropriate methods of proving this assumption, such as TEM and FIB, are required.
7
Xu, Jingsi M. C. P. Massachusetts Institute of Technology. "Energy intensity in China's iron and steel sector". Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/67246.
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Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2011.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 105-108).
In this study, I examine the spatial and economic factors that influence energy intensity in China's iron and steel sector, namely industrial value added, renovation investment, coke consumption, and local coke supply. Despite the recognition of the importance of these spatial and economic factors in understanding energy intensity in the steel industry, the municipal and provincial governments of China have failed to integrate them into their energy policy making. Therefore, in order to seek the most effective ways of reducing energy intensity and to encourage energy conservation behavior in China's iron and steel sector, I make three simulations based on the (1) shifts in direct energy efficiency in the sector, (2) coke consumption during the iron and steel making processes, and (3) manufacturing material transportation. I propose an analytical framework for examining the differences in energy intensity at the regional level that are attributed to these spatial and economic factors. More specifically, among these four key factors presented in the multi-level regression models, I identify three factors-industrial value added, renovation investment, and coke consumption indices- as "spatial-level" or "time-variant" factors. I treat the fourth one-local coke supply-as the only "temporal-level" or "time-invariant" factor. I present three major implications for the energy policy-making regarding the development of a "green" iron and steel sector in China. First, when I incorporate all four key factors-industrial value added, renovation investment, coke consumption, and local coke supply-I obtain significantly improved overall exploratory power of the regional-level energy intensity model. Second, the results of my national-level input-output analysis show that policy makers should focus on the changes in total energy intensity, which includes both direct (40 percent) and indirect (60 percent) energy intensity, to design, implement, and evaluate energy-efficient policies for China's iron and steel sector. Third, my study sheds light on the most recent national-level development plan the "1 2 th Five-Year' Plan-and I argue that by adopting efficient industrial structure upgrading strategies, the iron and steel sector can dramatically reduce the national energy consumption in China in the near future.
by Jingsi Xu.
M.C.P.
8
Ekengård, Johan. "Slag/Metal Metallurgy in Iron and Steel Melts". Doctoral thesis, KTH, Tillämpad processmetallurgi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-187228.
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In this work, the metal and slag phase mixing in three steps of a ladle refining operation of steel melts and for an oxygen balance during cooling of cast iron melts have been studied at two Swedish steel plants and at two Swedish cast iron foundries, respectively. In order to predict the oxygen activity in the steel bulk in equilibrium with the top slag as well as in metal droplets in the top slag in equilibrium with the top slag, three slag models were used. In addition, the assumptions of a sulphur-oxygen equilibrium between steel and slag and the dilute solution model for the liquid steel phase were utilized in the calculations. Measured oxygen activities in steel bulk, which varied between 3.5-6 ppm, were compared to predicted oxygen activities. The differences between the predicted and measured oxygen activities were found to be significant (0-500%) and the reasons for the differences are discussed in the thesis. Slag samples have been evaluated to determine the distribution of the metal droplets. The results show that the relatively largest numbers of metal droplets are present in the slag samples taken before vacuum degassing. Also, the projected interfacial area between steel bulk and top slag has been compared to the interfacial area between the metal droplets and slag. The results show that the droplet-slag interfacial area is 3 to 14 times larger than the flat projected interfacial area between the steel and top slag. Furthermore, the effect of the reactions between top slag and steel and the slag viscosity on the metal droplet formation is discussed. The results show significant differences between the steel bulk and steel droplet compositions and the reasons for the differences are discussed in the thesis. The oxygen activity in different cast irons was studied. Plant trials were performed at three occasions for lamellar, compacted and nodular iron melts. The results show that at temperatures close to the liquidus temperature the oxygen activities were 0.03-0.1 ppm for LGI, around 0.02 ppm for CGI, and 0.001ppm for SGI. In addition, it was found that as the oxygen activities increased with time after an Mg treatment, the ability to form a compact graphite or a nodular graphite in Mg-treated iron melts was decreased. Also, extrapolated oxygen activity differences up to 0.07 ppm were found for different hypoeutectic iron compositions for lamellar graphite iron at the liquidus temperature. Overall, the observed differences in the dissolved oxygen levels were believed to influence how graphite particles are incorporated into the austenite matrix and how the graphite morphology will be in the cast product.QC 20160518
9
Tognarelli, Donna M. "Heavy metal mobility in iron and steel waste". Thesis, University of the West of Scotland, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.742768.
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Ionescu, Denisa V. "The hydraulic potential of high iron bearing steel slags". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0018/NQ46358.pdf.
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Richardson, Hugh. "Iron and steel production and trade patterns in China /". Title page, contents and introduction only, 1990. http://web4.library.adelaide.edu.au/theses/09EC/09ecr522.pdf.
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Saleh, Abdel Fattah El Sayed. "Performance evaluation in the Egyptian iron and steel industry". Thesis, University of Hull, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297383.
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Sidhu, Mandeep Singh. "Liquid Aluminium Corrosion Characteristics of Cast Iron and Steel". Thesis, University of Canterbury. Mechanical Engineering, 2012. http://hdl.handle.net/10092/7013.
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Cast iron and steel alloys are commonly used for tooling and structural components in Al production, Al die-casting and the aluminizing industry due to their favourable properties including high strength, good formability and low cost. However, the iquid Al corrosion of these materials is one of the crucial concerns in maintaining the efficient production. Al is produced by the electrolytic smelting of alumina. Cast iron and/or cast steel pipes - commonly known as „tapping pipes‟ - are used to extract the liquid Al produced by smelting. Tapping pipes mainly degrade by material loss because liquid Al reacts with nearly all metals. Failure of tapping pipes is a significant contributor to the maintenance expenses; therefore, the primary aim of this research is to develop a material to enhance the life time of tapping pipes. Various test methods were developed in order to examine the effect of molten Al
environment on cast iron and steel alloys. The corrosion resistance of these alloys was determined under different conditions of Al flow and temperature. The intermetallic compounds formed by exposing the ferrous to liquid Al were characterized using the Energy Dispersive X-ray Spectroscopy (EDS) and Electron Back Scatter Diffraction (EBSD) techniques. The formation, growth and nature of reaction products were revealed to establish a link to the liquid Al corrosion resistance. A relationship between the chemical composition and liquid Al corrosion resistance of cast irons could not established in the past. In the present work, the corrosion rate was found to depend upon the graphite morphology and fraction of each Fe-C phase of cast
iron matrix, which can be controlled by selecting the chemical composition. Moreover, present research suggested the guidelines for producing a cast iron with enhanced liquid
Al corrosion resistance. The presence of C-rich phases, graphite flakes and cementite was found to be effective in enhancing the liquid Al corrosion resistance of gray cast
irons. Conversely, a higher Si content was found to enhance the susceptibility of cast irons to liquid Al corrosion.
The corrosion mechanisms for ferrous alloys in liquid Al are not fully understood. Thus the subsequent analysis of the dissolution data was supported by investigating the
reaction products formed between Al and substrate materials. In addition to commonly existent ε-Fe2Al5 and ζ-FeAl3 phases, the formation of Al4C3 and κ-Fe3AlC compounds was confirmed for the first time in the intermetallic layers of ferrous alloys. The Fe3Si phase in the intermetallic layers of high Si cast irons was found, which was believed to facilitate the high corrosion rates of high Si cast irons. Moreover, the mechanism by which C in Fe-substrates affects the liquid Al corrosion resistance can be better understood given the present work.
Furthermore, the analysis presented here gives an understanding of the nature, growth and dissolution of intermetallic compounds in several cast iron alloys. Higher Si
additions to cast irons played an important role in molten metal corrosion by accelerating the material loss and changing the nature of intermetallic layers. The results of this study
clearly indicated that the dissolution and the growth of intermetallic compounds are interrelated and the dissolution and/or spallation of the intermetallic layers may be the
primary mode of liquid Al corrosion of ferrous alloys.
14
Bienias, Grzegorz. "An experimental investigation of the shear plate connections". Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26682.
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In Limit States Design for steel structures, single plate connections are designed to transfer beam shear to supporting member. These connections, with the connection plate shop-welded to the supporting member and field-bolted to the supported beam are becoming increasingly popular due to their economy and ease of fabrication. Single plate connections are very suitable for cases where speed of erection is a primary consideration. They are particularly superior for skewed connections. Traditional design methods which deal with connection problems generally give over-conservative solutions to this complex problem.
Two series of experimental investigations of single plate connections for beam-to-girder webs were conducted. A variety of connections were tested to demonstrate their feasibility and to collect data for analytical correlation studies. The ultimate goal of these tests and studies is to devise a rational basis for the design of these connections. This work is part of a comprehensive research project and the reader is referred to other papers (References 1 and 2) for completeness.
Based on experimental results and theoretical correlation studies, a modified design formula is proposed in order to predict the ultimate capacity of single plate connections. The formula tries to incorporate the influences of applied loads (shear force, torsional moment, and bending moment), resistance of the single plate connection, skew angle of the connection plate and type of holes (slotted and standard) used in the connection.Applied Science, Faculty of
Civil Engineering, Department of
Graduate
15
Huang, Donglin. "Heterogeneous reduction of selenite by zero valent iron-steel wool". Morgantown, W. Va. : [West Virginia University Libraries], 2010. http://hdl.handle.net/10450/11233.
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Thesis (Ph. D.)--West Virginia University, 2010.Title from document title page. Document formatted into pages; contains ix, 106 p. : ill. (some col.). Includes abstract. Includes bibliographical references.
16
Georgakopoulos, Evangelos D. "Iron and steel slag valorization through carbonation and supplementary processes". Thesis, Cranfield University, 2016. http://dspace.lib.cranfield.ac.uk/handle/1826/12323.
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Alkaline industrial wastes are considered potential resources for the mitigation of CO2 emissions by simultaneously capturing and sequestering CO2 through mineralization. Mineralization safely and permanently stores CO2 through its reaction with alkaline earth metals. Apart from natural formations, these elements can also be found in a variety of abundantly available industrial wastes that have high reactivity with CO2, and that are generated close to the emission point-sources. Apparently, it is the applicability and marketability of the carbonated products that define to a great extent the efficiency and viability of the particular process as a point source CO2 mitigation measure. This project investigates the valorization of iron- and steel-making slags through methods incorporating the carbonation of the material, in order to achieve the sequestration of sufficient amounts of CO2 in parallel with the formation of valuable and marketable products. Iron- and steel-manufacturing slags were selected as the most suitable industrial byproducts for the purposes of this research, due to their high production amounts and notable carbonation capacities. The same criteria (production amount and carbonation capacity) were also used for the selection of the iron- and steel-making slag types that are more suitable to the scope of this work. Specifically for the determination of the slag types with the most promising carbonation capacities, the maximum carbonation conversions resulting from recent publications related to the influence of process parameters on the conversion extent of iron- and steel-manufacturing slags, were directly compared to each other using a new index, the Carbonation Weathering Rate, which normalizes the results based on particle size and reaction duration. Among the several iron- and steel-manufacturing slags, basic oxygen furnace (BOF) and blast furnace (BF) slags were found to combine both high production volumes and significant affinity to carbonation. In the context of this research, two different procedures aiming to the formation of value added materials with satisfactory CO2 uptakes were investigated as potential BF and BOF slags valorization methods. In them, carbonation was combined either with granulation and alkali activation (BOF slag), or with hydrothermal conversion (BF slag). Both treatments seemed to be effective and returned encouraging results by managing to store sufficient amounts of CO2 and generating materials with promising qualities. In particular, the performance of the granulation-carbonation of BOF slag as a method leading to the production of secondary aggregates and the sequestration of notable amounts of CO2 in a solid and stable form, was evaluated in this work. For comparison purposes, the material was also subjected to single granulation tests under ambient conditions. In an effort to improve the mechanical properties of the finally synthesized products, apart from water, a mixture of sodium hydroxide and sodium silicate was also tested as a binding agent in both of the employed processes. According to the results, the granules produced after the alkali activation of the material were characterized by remarkably greater particle sizes (from 1 to 5 mm) compared to that of the as received material (0.2 mm), and by enhanced mechanical properties, which in some cases appeared to be adequate for their use as aggregates in construction applications. The maximum CO2 uptake was 40 g CO2/kg of slag and it was achieved after 60 minutes of the combined treatment of alkali activated BOF slag. Regarding the environmental behavior of the synthesized granules, increased levels of Cr and V leaching were noticed from the granules generated by the combination of granulation-carbonation with alkali activation. Nevertheless, the combination of granulation with alkali activation or that of granulation with carbonation were found not to worsen, if not to improve, the leaching behaviour of the granules with regards to the untreated BOF slag. The formation of a zeolitic material with notable heavy metal adsorption capacity, through the hydrothermal conversion of the solid residues resulting from the calcium- extraction stage of the indirect carbonation of BF slag, was also investigated in this project. To this end, calcium was selectively extracted from the slag by leaching, using acetic acid of specific concentration (2 M) as the extraction agent. The residual solids resulting from the filtration of the generated slurry were subsequently subjected to hydrothermal conversion in caustic solution of two different compositions (NaOH of 0.5 M and 2 M). Due to the presence of calcium acetate in the composition of the solid residues, as a result of their inadequate washing, only the hydrothermal conversion attempted using the sodium hydroxide solution of higher concentration (2 M) managed to turn the amorphous slag into a crystalline material, mainly composed by a zeolitic mineral phase (detected by XRD), namely, analcime (NaAlSi2O6·H2O), and tobermorite (Ca5(OH)2Si6O16·4H2O). Finally, the heavy metal adsorption capacity of the particular material was assessed using Ni2+ as the metal for investigation. Three different adsorption models were used for the characterization of the adsorption process, namely Langmuir, Freundlich and Temkin models. Langmuir and Temkin isotherms were found to better describe the process, compared to Freundlich model. Based on the ability of the particular material to adsorb Ni2+ as reported from batch adsorption experiments and ICP-OES analysis, and the maximum monolayer adsorption capacity (Q0 = 11.51 mg/g) as determined by the Langmuir model, the finally synthesized product can potentially be used in wastewater treatment or environmental remediation applications.
17
Nhamoinesu, Shelton. "Steel-glass composite panels". Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708845.
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Datta, Satya Brata. "Capital accumulation and workers' struggle in Indian industrialisation : the case of Tata Iron and Steel Company 1910-1970". Doctoral thesis, Stockholm : Almqvist & Wiksell International, 1986. http://catalog.hathitrust.org/api/volumes/oclc/15397056.html.
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Hillman, John R. "Innovative lightweight floor systems for steel framed buildings". Thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-06082009-170953/.
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Kuyucak, Selçuk. "Direct detection of non-metallic inclusions in molten iron". Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63356.
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Armstrong, Derek C. "Influence of segregated impurities on the corrosion and oxidation of ferrous alloys". Thesis, University of Cambridge, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239600.
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Hewetson, C. G. "Object - oriented steel member design framework /". Thesis, Link to the online version, 2005. http://hdl.handle.net/10019/249.
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Clingenpeel, Beth F. "The economical use of high performance steel in slab-on-steel stringer bridge design". Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=2235.
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Thesis (M.S.)--West Virginia University, 2001.Title from document title page. Document formatted into pages; contains xiii, 148 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 136-137).
24
Li, Guzhao. "Bracing design requirements for inelastic members". Access restricted to users with UT Austin EID, 2002. http://www.lib.utexas.edu/etd/r/d/2002/guzhaol022/guzhaol022.pdf#page=4.
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Lui, Wing Man. "Design of cold-formed high strength stainless steel tubular columns and beam-columns /". View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?CIVL%202004%20LUI.
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Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2004.Includes bibliographical references (leaves 149-154). Also available in electronic version. Access restricted to campus users.
26
Öhman, Amanda. "Towards a fossil free steel sector : Conditions for technology transfer of hydrogenbased iron and steel in Europe". Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-264106.
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In order to meet the targets of the Paris Agreement, there is a need to significantly reduce emissions from energy-intensive industries, iron and steel included. One promising technology with the potential to reduce the emissions related to iron and steelmaking to basically none is direct reduction with fossil free hydrogen, which requires large amounts of fossil free electricity. This master thesis explores the conditions for this technology in a European context with an energy perspective as the main focus. Three primary steel producing countries in Europe are chosen as focus countries; Germany, France and Italy. The findings of the study conclude that neither of the focus countries is an optimal sociotechnical fit for hydrogen-based direct reduction for iron and steel production at present. France is the country with the best conditions from a solely energy perspective but lacks some important factors for an enabling environment for technology transfer. Germany on the other hand have the most promising characteristics for an enabling environment but still face large challenges when it comes to power sector decarbonisation. In order to overcome the barriers and create an enabling environment it is key that energy and industry transitions are aligned, that a policy framework that supports these transitions is in place and that key actors representing all aspects of the transition cooperate; from industry to research, academia, policymakers and others. The findings also show that the current locations of the primary steel plants are in many cases not where the most favourable conditions for renewable power generation are and given the renewable capacity and transmission limitations of today, merely switching to a hydrogenbased process is not likely viable. A future configuration could be decentralised value chains where the different processes are located where there are optimal conditions e.g. that either hydrogen or sponge iron is produced where there are favourable power conditions and then transported to steel plants for the remaining processes in the value chain.För att nå målen uppsatta i Parisavtalet behöver energiintensiva industrier kraftigt minska sina utsläpp, däribland järn- och stålindustrin. Direktreduktion med fossilfri vätgas är en teknologi med potential att minska utsläppen från järn och ståltillverkning till praktiskt taget noll men kräver stora mängder fossilfri el. Detta examensarbete undersöker de energimässiga förutsättningarna för denna teknik i en europeisk kontext. Tre länder som producerar primärstål är utvalda som fokusländer i studien; Tyskland, Frankrike och Italien. Resultaten av studien visar att inget av de utvalda länderna i dagsläget har optimala sociotekniska förutsättningar för tekniken. Frankrike är det land med de bästa energimässiga förutsättningarna men saknar några viktiga faktorer för att vara en möjliggörande socioteknisk miljö. Tyskland å andra sidan har de mest lovande förutsättningarna för en lämplig socioteknisk miljö men står inför utmaningar när det kommer till energisystemet och tillgången på fossilfri el. För att skapa förutsättningar för denna teknik är det viktigt med koordinerade omställningar i energisektorn och industrin, policys som möjliggör dessa omställningar samt ett väl fungerande samarbete mellan industrin, akademin, beslutsfattare och andra viktiga aktörer. Studien visar också att de platser där nuvarande stålverk för primärstål finns inte har de bästa förutsättningar för förnybar elproduktion och att en vätgasbaserad process inte är optimal, baserat på den förnybara kapaciteten och de transmissionsbegränsningar som finns idag i elsystemet. Det finns istället möjlighet till decentraliserade värdekedjor, där varje process placeras där de mest lämpliga förhållandena finns. Detta kan exempelvis innebära att vätgas eller järnsvamp produceras där tillgången till fossilfri el är god, för att sedan transporteras till stålverken för de resterande processtegen.
27
Ruminski, Clayton J. "Iron Valley: Transition and Evolution of Merchant Iron Producers in the Youngstown District, 1845-1967". Youngstown State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1370003488.
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Inegbenebor, A. O. "Structure-property relationships in some iron-manganese-molybdenum steels". Thesis, Bucks New University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380862.
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MacInnes, A. N. "The interlayer formed between iron and an acrylic latex". Thesis, University of Surrey, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.290482.
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Jãuregui, David Villegas. "Measurement-based evaluation of non-composite steel girder bridges /". Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.
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Sorbello, Fabio. "Role of interfaces on the fracture resistance of iron-silicon steel". Thesis, University of Bristol, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492598.
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Liu, Xiaoling. "The decopperization and detinning of iron and steel by sulphide treatment". Thesis, Imperial College London, 1987. http://hdl.handle.net/10044/1/47115.
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Kharel, Govinda Prasad. "Evaluation of eco-efficiency of iron and steel industries in Nepal /". Abstract, 2006. http://mulinet3.li.mahidol.ac.th/thesis/2549/cd397/4837462.pdf.
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Yonekura, Seiichirō. "The Japanese iron and steel industry, 1850-1990 : continuity and discontinuity /". Basingstoke : New York : MacMillan ; St. Martin's press, 1995. http://catalogue.bnf.fr/ark:/12148/cb37477905c.
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Kalcioglu, Ali Ferdi 1960. "Distribution of antimony between carbon-saturated iron and blast furnace slags". Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277129.
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Understanding the effects of the process parameters on the distribution behaviour of antimony between metal and slag in the iron blast furnace is critical to develop a universal method of controlling temper embrittlement in commercially pure low alloy steels.
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Hedayati, Mohammad Hassan. "Performance-based design of stainless steel blast walls". Thesis, University of Aberdeen, 2018. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=239895.
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Stainless steel profiled walls have increasingly been used in the process and other industries to protect people and personnel against hydrocarbon or chemical explosions. The existence of various uncertainties, in particular the ones associated with explosion loading and parameters, make the current design and assessment which are based on single degree of freedom (SDOF) and deterministic approach, very complicated and in many cases leading to unreliable design assessment. Therefore, developing an appropriate reliability approach for assessing and designing blast wall structures would greatly assist in improving the safety of personnel and plant facilities. The objective of this research study is to develop a practical framework for performance based design of stainless steel profiled barrier blast walls, with specific focus on reliability assessment by implementing stochastic finite element analysis (SFEA). Initially, the current traditional SDOF method is reviewed to identify the related issues and weaknesses and accordingly an appropriate method for structural assessments of the blast walls is proposed. Furthermore, a comprehensive investigation on various available methods is carried out to identify a suitable probabilistic approach for the reliability assessments. The corresponding reliability of these structures is evaluated with a MCS method, implementing the Latin Hypercube Sampling (LHS) approach. A programming package is developed using Ansys Parametric Design Language (APDL), to generate parametric finite element models and to perform automated reliability assessments. The significant uncertainties are combined with an advanced analysis model to investigate the influence of loading, material and geometric uncertainties on the response of these structures under realistic boundary conditions and connection configuration. Effective implementation of the framework is achieved by the development of a combined programming package to deal with both finite element and reliability analyses. A further development for this research study is associated with the development of performance based design approach, using the results of the probabilistic and finite element assessments. This can be utilised for optimum and appropriate design of the blast wall structures, based on the defined performance levels. Application and practicality of the developed approach and associated programming package is demonstrated through a number of case studies of realistic stainless steel profiled barriers subject to explosion loading. The results of the preliminary probabilistic case studies confirm that the explosion loading is the main influential input parameter and also nonlinearities are more critical than dynamic effects for unstiffened profiled barrier blast walls. An appropriate dynamic load factor (DLF) is proposed for the preliminary stage of the design and assessments. It is observed that using the probabilistic approach can help identify the important variables and parameters to optimize the design of profiled blast walls, and to perform risk assessments for these structures. The study is expanded to develop a performance based design methodology, linking the probabilistic results with various performance levels and associated parameters (e.g., damage levels). The results and discussions of the case studies associated with performance based design assessments confirm the suitability of the proposed framework, and also highlight the complications in defining intermediate levels, without preliminary investigations. This shows that QRA approach and involvement of professionals can play an important role to develop performance levels and the associated objectives. The developed programming package and associated framework are expected to provide valuable guidance to professional design engineers and researchers, by obviating the need for complex computational requirements.
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Al-Shihri, Marai Abdullah 1958. "BUCKLING STRENGTH OF HEAVY STEEL COLUMNS (WELDED SHAPES, INITIAL CURVED COLUMNS, HOT-ROLLED SHAPES)". Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/291869.
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Medina, Ricardo A. Krawinkler Helmut. "Seismic demands for nondeteriorating frame structures and their dependence on ground motions /". Berkeley : Pacific Earthquake Engineering Research Center, 2004. http://peer.berkeley.edu/publications.
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Originally published as first author's thesis."May 2004." "John A. Blume Earthquake Engineering Center, Dept. of Civil & Environmental Engineering, Stanford University." Includes bibliographical references.
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Kerr, Robert A. "Connection limit states design teaching aid". Master's thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-10242009-020036/.
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Juleff, Gillian. "Early iron and steel in Sri Lanka : a study of the Samanalawewa area". Thesis, University College London (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285198.
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Vieira, Rodrigo Cuberos 1983. "Estudo comparativo entre terças de aço, convencionais em vigas, em treliças planas e em treliças multiplanares". [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257811.
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Orientador: João Alberto Venegas RequenaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo
Made available in DSpace on 2018-08-14T15:27:42Z (GMT). No. of bitstreams: 1 Vieira_RodrigoCuberos_M.pdf: 3840052 bytes, checksum: b4860daa77b57af17db9c3c0885bb512 (MD5) Previous issue date: 2009
Resumo: As coberturas metálicas são muito utilizadas em edificações que necessitam de grandes espaços internos livres e possuem um prazo de execução pequeno, como por exemplo, galpões comerciais, industriais e centros de armazenamento e distribuição. Dentre as suas partes constituintes, as terças são responsáveis por uma parcela considerável do peso total da cobertura. Neste trabalho foi desenvolvido um amplo estudo sobre os diversos tipos de terças metálicas utilizadas em estruturas metálicas de médio e grande porte, com vãos de até 40 metros, abordando as terças em perfil laminado e formado a frio, e as terças treliçadas em perfis abertos e tubulares. Foram realizados estudos aprofundados sobre o dimensionamento de terças em perfil laminado e formado a frio, com o desenvolvimento de um programa de verificação e dimensionamento para esses tipos de terças. Também foram realizados estudos sobre o dimensionamento de terças treliçadas planas, também conhecidas como joists, que já têm a sua utilização bastante difundida, e de terças treliçadas tubulares multiplanares, cuja utilização ainda é pequena se comparada com os demais tipos de terças. Com esses estudos, foram feitas análises comparativas para diversos vãos, com as ações comumente utilizadas em estruturas que possuem coberturas metálicas, possibilitando identificar qual o tipo de terça mais adequado para cada situação estudada. Uma análise dos custos das terças também foi realizada, permitindo verificar a viabilidade da utilização das terças treliçadas tubulares em coberturas metálicas, principalmente das terças treliçadas tubulares multiplanares, cuja aplicação ainda é pequena.
Abstract: Steel roof systems are widely used in buildings that require large free internal spaces and small execution times, such as commercial and industrial warehouses and storage and distribution centers. The purlins have a considerable contribution in the roof system total weight composition. In this work was developed a study on the different types of purlins for medium and large spans, up to 40 meters, analyzing the hot-rolled sections, cold-formed sections and trusses with open or hollow sections. Purlin design studies were conducted for hot-rolled and cold-formed sections, with a computational software development for these purlin types. The use of planar trusses as purlins, also called steel joists, is already well known, and its design was studied too, as well as the multi-planar tubular trusses, whose use is still small when compared with the other purlin types. With these studies, a comparative analysis was made for various spans, applying the loads commonly used in steel roof systems, allowing the investigation of the best purlin type for each proposed situation. An analysis of the purlin costs was also performed, allowing to study the feasibility of the tubular trusses use in steel roof systems, especially the multi-planar tubular trusses, whose application is still small.
Mestrado
Estruturas
Mestre em Engenharia Civil
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Dogo, Harun. "Point defect properties in iron chromium alloys". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2006. http://library.nps.navy.mil/uhtbin/hyperion/06Sep%5FDogo.pdf.
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Thesis (M.S. in Applied Physics)--Naval Postgraduate School, September 2006.Thesis Advisor(s): Craig Smith, Xavier Maruyama. "September 2006." Includes bibliographical references (p. 57-59). Also available in print.
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Adolfi, Sofia. "Slag inclusion formation during solidification of steel alloys and in cast iron". Licentiate thesis, Stockholm : Materialvetenskap, Kungliga Tekniska högskolan, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4371.
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Bowman, John Frederick. "The iron and steel industries of the Derwent Valley : a historical archaeology". Thesis, University of Newcastle upon Tyne, 2018. http://hdl.handle.net/10443/4145.
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Within the Derwent valley, to the south east of Newcastle-upon-Tyne, lies the Derwentcote Historic Landscape. The site consists of three historical monuments, a forge, a steel furnace and a row of worker's cottages which are in the stewardship of Historic England. This thesis asks how the Derwentcote Iron and Steel works operated within the overall iron working landscape of the Derwent valley. The thesis examines for the first time the archaeology of a pioneering iron industry scattered throughout the whole of a valley which is geographically divided between the counties of Northumberland, Durham and Tyne and Wear. A multifaceted, interdisciplinary approach has been employed utilising a wide variety of primary sources and drawing on several techniques developed by historical archaeologists. Documentary sources and archaeological data have been integrated in considering the archaeological landscape, while process recording and a modification of the Manchester Methodology have been used to assess technological and social developments. A detailed artefact biography has been carried out on Derwentcote as it is the most complete site in the valley. The results of this research have been georeferenced within a GIS. The findings of the thesis indicate that within the Derwent Valley three periods of iron working can be identified: a pre-industrial period, commencing historically in 1299, of local landowners producing iron for their own use, the Industrial Revolution, which arrived in the valley c.1687 through external entrepreneurial interests, and the steam-driven Machine Age which exploited new ore seams and technologies from 1840. The research indicates that the Derwentcote may have operated within all three phases. The valley often adopted the latest technologies in ironworking. Physical evidence for each of these phases remains scattered throughout the area today. The case study of the site of Derwentcote has proven to be a technical microcosm of the national industry.
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Johansson, Maria. "Improved Energy Efficiency and Fuel Substitution in the Iron and Steel Industry". Doctoral thesis, Linköpings universitet, Energisystem, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-105849.
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IPCC reported in its climate change report 2013 that the atmospheric concentrations of the greenhouse gases (GHG) carbon dioxide (CO2), methane, and nitrous oxide now have reached the highest levels in the past 800,000 years. CO2 concentration has increased by 40% since pre-industrial times and the primary source is fossil fuel combustion. It is vital to reduce anthropogenic emissions of GHGs in order to combat climate change. Industry accounts for 20% of global anthropogenic CO2 emissions and the iron and steel industry accounts for 30% of industrial emissions. The iron and steel industry is at date highly dependent on fossil fuels and electricity. Energy efficiency measures and substitution of fossil fuels with renewable energy would make an important contribution to the efforts to reduce emissions of GHGs. This thesis studies energy efficiency measures and fuel substitution in the iron and steel industry and focuses on recovery and utilisation of excess energy and substitution of fossil fuels with biomass. Energy systems analysis has been used to investigate how changes in the iron and steel industry’s energy system would affect the steel plant’s economy and global CO2 emissions. The thesis also studies energy management practices in the Swedish iron and steel industry with the focus on how energy managers think about why energy efficiency measures are implemented or why they are not implemented. In-depth interviews with energy managers at eleven Swedish steel plants were conducted to analyse energy management practices. In order to show some of the large untapped heat flows in industry, excess heat recovery potential in the industrial sector in Gävleborg County in Sweden was analysed. Under the assumptions made in this thesis, the recovery output would be more than three times higher if the excess heat is used in a district heating system than if electricity is generated. An economic evaluation was performed for three electricity generation technologies for the conversion of low-temperature industrial excess heat. The results show that electricity generation with organic Rankine cycles and phase change material engines could be profitable, but that thermoelectric generation of electricity from low-temperature industrial excess heat would not be profitable at the present stage of technology development. With regard to fossil fuels substituted with biomass, there are opportunities to substitute fossil coal with charcoal in the blast furnace and to substitute liquefied petroleum gas (LPG) with bio-syngas or bio synthetic natural gas (bio-SNG) as fuel in the steel industry’s reheating furnaces. However, in the energy market scenarios studied, substituting LPG with bio-SNG as fuel in reheating furnaces at the studied scrap-based steel plant would not be profitable without economic policy support. The development of the energy market is shown to play a vital role for the outcome of how different measures would affect global CO2 emissions. Results from the interviews show that Swedish steel companies regard improved energy efficiency as important. However, the majority of the interviewed energy managers only worked part-time with energy issues and they experienced that lack of time often was a barrier for successful energy management. More efforts could also be put into engaging and educating employees in order to introduce a common practice of improving energy efficiency at the company.Halterna av växthusgaserna koldioxid (CO2), metan och kväveoxider har under de senaste 800 000 åren aldrig varit högre i atmosfären än vad de är idag. Detta resultat redovisades i IPCCs klimatrapport år 2013. CO2-koncentrationen har ökat med 40 % sedan förindustriell tid och denna ökning beror till största delen på förbränning av fossila bränslen. Ökade koncentrationer av växthusgaser leder till högre global medeltemperatur vilket i sin tur resulterar i klimatförändringar. För att bromsa klimatförändringarna är det viktigt att vi arbetar för att minska utsläppen av växthusgaser. Industrin står för 20 % av de globala utsläppen av CO2 och järn- och stålindustrin står för 30 % av industrins utsläpp. Järn- och stålindustrin är i dag till stor del beroende av fossila bränslen och el för sin energiförsörjning. Energieffektiviseringsåtgärder och byte av fossila bränslen mot förnybar energi i järn- och stålindustrin skulle kunna bidra till minskade utsläpp av växthusgaser. Denna avhandling studerar åtgärder för effektivare energianvändning och möjligheter för bränslebyte i järn- och stålindustrin. Avhandlingen fokuserar på återvinning och utnyttjande av överskottsenergier och ersättning av fossila bränslen med biomassa. Energisystemanalys har använts för att undersöka hur förändringar i järn- och stålindustrins energisystem skulle påverka ekonomin och de globala utsläppen av CO2. Avhandlingen studerar också betydelsen av energiledning och nätverkande för att uppnå en effektivare energianvändning. Fokus har här varit på att studera hur energiansvariga resonerar kring varför energieffektiviseringsåtgärder genomförs eller varför de inte genomförs. Djupintervjuer med energiansvariga vid elva svenska stålverk genomfördes för att analysera denna fråga. För att ge ett exempel på den stora outnyttjade potentialen av överskottsvärme från industrin analyserades potentialen i Gävleborgs län. Möjligheterna att använda överskottsvärmen som fjärrvärme eller för att producera el analyserades. Här visar resultaten att fjärrvärmeproduktionen skulle bli mer än tre gånger så stor som elproduktionen. En ekonomisk utvärdering gjordes där tre tekniker för produktion av el från lågtempererad industriell överskottsvärme jämfördes. Resultaten visar att elproduktion med organisk Rankine-cykel eller en så kallad fasändringsmaterialmotor kan vara lönsam, men att termoelektrisk elproduktion inte är lönsam med dagens teknik och prisnivåer. Det är möjligt att ersätta en del av det fossila kolet i masugnen med träkol och på detta sätt introducera förnybar energi i stålindustrin. Man kan också ersätta gasol som används som bränsle i stålindustrins värmningsugnar med syntesgas eller syntetisk naturgas (SNG) som produceras genom förgasning av biomassa. Under de antaganden som gjorts i avhandlingen skulle det dock inte vara lönsamt för det skrotbaserade stålverk som studerats att ersätta gasolen med bio-SNG. För att uppnå lönsamhet behövs i detta fall ekonomiska styrmedel. Hur olika åtgärder påverkar de globala utsläppen av CO2 beror till stor del på hur framtidens energimarknad ser ut. Elproduktion från industriell överskottsvärme skulle minska de globala CO2-utsläppen i alla scenarier som studerats, men för de andra åtgärderna varierar resultaten beroende på vilka antaganden som gjorts. Resultaten från intervjustudien visar att svensk stålindustri anser att energifrågan är viktig, men det finns fortfarande mycket att göra för att effektivisera energianvändningen i denna sektor. Flera av de intervjuade arbetade bara deltid med energifrågor och de upplevde att tidsbrist hindrade dem från ett effektivt energiledningsarbete. En rekommendation till företagen är därför att anställa en energiansvarig på heltid och/eller fler personer som kan arbeta med energifrågor. Det bör också läggas mer resurser på att engagera och utbilda anställda för att på så sätt introducera en företagskultur som främjar effektiv energianvändning.
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Ning, Jing. "The Role of Iron Sulfide Polymorphism in Localized Corrosion of Mild Steel". Ohio University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1476660078407962.
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Navabzadeh, Esmaeely Saba. "Galvanic Localized Corrosion of Mild Steel under Iron Sulfide Corrosion Product Layers". Ohio University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou151551709542735.
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Baselli, Silvia. "Study of the anisotropic sintering shrinkage of green iron and stainless steel". Doctoral thesis, Università degli studi di Trento, 2020. http://hdl.handle.net/11572/267476.
Texto completoResumen
Powder metallurgy (PM) is a near net-shape technology that guarantees excellent dimensional control and surface finishing in the production of parts with complex shapes. Press and sinter is the conventional PM process. The powder mix is compacted into rigid dies to obtain the so called green part that is subsequently sintered to promote the formation of metallic bonding between the powder particles. The differences in terms of geometrical and dimensional features between the green compact and the final part are related to the dimensional variations occurring during sintering, therefore, to preserve the cost effectiveness of the process, their in-depth knowledge is crucial. In this context, post- sintering machining should be limited to the realization of geometrical details that cannot be directly obtained through uniaxial cold compaction or to achieve strict tolerances required by specific applications. The dimensional changes in sintering that may be either shrinkages or swellings are affected by many parameters and, among them, we can consider: material, presence of lubricant and additives, green density, compaction strategy, sintering temperature and time, atmosphere, heating and cooling rate. Furthermore, the dimensional variations along the direction parallel to compaction (longitudinal, axial) are different from the dimensional variations in the compaction plane (transversal, radial) causing an anisotropy that depends, in addition to the mentioned parameters, on the geometry and the dimension of the part. At present, in absence of an adequate designing tool to account for the anisotropy, engineers rely on empirical methods often based on the trial-and-error approach.
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Baselli, Silvia. "Study of the anisotropic sintering shrinkage of green iron and stainless steel". Doctoral thesis, Università degli studi di Trento, 2020. http://hdl.handle.net/11572/267476.
Texto completoResumen
Powder metallurgy (PM) is a near net-shape technology that guarantees excellent dimensional control and surface finishing in the production of parts with complex shapes. Press and sinter is the conventional PM process. The powder mix is compacted into rigid dies to obtain the so called green part that is subsequently sintered to promote the formation of metallic bonding between the powder particles. The differences in terms of geometrical and dimensional features between the green compact and the final part are related to the dimensional variations occurring during sintering, therefore, to preserve the cost effectiveness of the process, their in-depth knowledge is crucial. In this context, post- sintering machining should be limited to the realization of geometrical details that cannot be directly obtained through uniaxial cold compaction or to achieve strict tolerances required by specific applications. The dimensional changes in sintering that may be either shrinkages or swellings are affected by many parameters and, among them, we can consider: material, presence of lubricant and additives, green density, compaction strategy, sintering temperature and time, atmosphere, heating and cooling rate. Furthermore, the dimensional variations along the direction parallel to compaction (longitudinal, axial) are different from the dimensional variations in the compaction plane (transversal, radial) causing an anisotropy that depends, in addition to the mentioned parameters, on the geometry and the dimension of the part. At present, in absence of an adequate designing tool to account for the anisotropy, engineers rely on empirical methods often based on the trial-and-error approach.
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Chmielowiec, Mark 1955. "MOMENT ROTATION CURVES FOR PARTIALLY RESTRAINED STEEL CONNECTIONS". Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/276452.
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Tension and Compression force deformation data from laboratory tests of angle segments are used to generate moment rotation curves for the following bolted partially restrained connections: (1) top and seat angle, (2) double web angle, and (3) top and seat angle with double web angles. The force deformation and moment rotation curves are analytically described by a four parameter formula which provides the basis for the analytical connection model. These connection models consist of rigid bars and nonlinear springs representing the angle segments in either tension or compression. Design curves giving the four parameters of the moment rotation curves are generated for the double web angle connection. These parameters are primarily a function of the angle thickness, gage length of the angle legs in flexture, and the number of bolts in the connection. Comparisons of derived moment rotation curves are made with published results of full scale tests.