Loughborough University, UK
Substantial research has been done in recent decades to improve on the basic first choice materials for modern power plant for the production of electricity. Two basic technologies will be reviewed: fossil fuel fired plant; and nuclear plant.
For fossil fired plant the most extreme conditions are to be found in the super heaters and top-end boilers. Materials for this application require high temperature (650°C) strength, oxidation resistance, good thermal conductivity, and low thermal expansion. High alloy ferritic steels with 9-12% Cr are used with grade names such as P91 and P92, HT9, or 1.4914. Development has centred on providing better high temperature strength. This has demanded the use of strong carbide forming elements such as Nb and V, and solution strengthening elements such as Mo and W, but higher carbon is avoided because of weldability issues. High nitrogen combines with strong carbide formers to form Z phase, which, along with sigma phase, limits the stress rupture life. This situation can be improved by redistributing the Z phase or other very stable phases such as HfC, in very fine particulate form, producing very high creep life materials. Advanced heat treatments can also improve creep strength in the ferritic steels. Higher temperatures than 650°C are now being considered, and nickel based alloys, such as IN 618 and 740 are the only materials which will offer the combination of high temperature strength and corrosion resistance required.
Nuclear plant that have undergone the most extensive materials research in recent times are: 1) the light water fission reactors; and 2) fusion tokamak systems.
The light water reactors consist of Zircaloy-clad uranium or plutonium fuel in high pressure water that is contained within a mild steel pressure vessel. These materials have generally performed well in the light water reactors, although there have been some concerns to limit the phosphorus levels in the pressure vessel steels to below 0.001% to prevent embrittling radiation-induced grain boundary phosphorus segregation. Copper precipitation during irradiation at operating temperatures of 300°C has also caused some embrittlement problems. The steam generators have generally relied on Alloys 600 and 690 nickel based alloys. In recent years an alloy more resistant to inter granular stress corrosion cracking, Alloy 625, has been employed.
Fusion reactors present perhaps the most formidable conditions for materials of any of the currently considered power plant systems. The first wall constructional material in the test reactor ITER (International Thermonuclear Experimental Reactor) will eventually be a ferritic steel based on the 9% Cr composition of 1.4914 or P92. One materials development that has accompanied the development of ITER is the production of the worldʼs first reduced activation steel, Eurofer97, which has the long half-life radioactive elements, Co, Ni, Nb and Mo removed. Another development is a novel heat treatment for this steel which reduces the DBTT to acceptably low temperatures (≤ -20°C).
Professor Roy Faulkner (Loughborough Materials Ltd) has been involved with nuclear reactor materials research for almost three decades. He was employed as a consultant to UKAEA, Harwell from 1980-90, and has led are search group interested in nuclear reactor materials at Loughborough University since 1990, with funding support from Rolls Royce Naval Marine, EDF, Magnox, EPSRC, and Oak Ridge National Laboratories. His interests are in breeder blanket ferritic ODS steel development for fusion, radiation-induced grain boundary segregation of P in Pressure vessel steels, and radiation induced chromium depletion in austenitic steels. Non- irradiation based interests, but still relevant to the current project proposal, are thermally induced chromium depletion modeling and experimental validation in Alloys 600 and 690, modeling and validation of micro structural evolution in ferritic and austenitic steels, and nickel base alloys, and its relation to creep and fracture toughness properties in these alloys. His overall mission is to provide, by modelling, a better understanding of micro structural changes occurring in high alloy steels and nickel based alloys in irradiation and high temperature environments. This mission is supported by a strong experimental expertise in high resolution microscopy techniques, most of which are available in the Loughborough Materials Characterisation Centre. He is Past-President of the East Midlands Metallurgical Society, Chairman of the IOM3 Publications Committee, and past Chairman of the IOM3 Younger Members Committee. He is also Past-Chairman of the Midlands Microanalysis Group.
Mechanical Power Engineering Department, Cairo University, Egypt
Studies that investigate the environmental health risks to Cairo residents showed that lead is one of the areaʼs major health hazards. Several references report ambient lead levels is up to 10 μg/m3 in many areas of Cairo and in the range of 10-50 μg/m3 in industrial areas. Studies of blood lead levels in Cairo residentʼs report that some children, the most sensitive receptors in the population, have blood lead concentrations up to three times the “safe” level. Many efforts have been done to reduce the ambient lead concentrations, and contamination with lead in industrial areas. The degree of lead levels in the atmospheric air in the greater Cairo area is discussed, the analysis showed that lead emitted to the atmospheric air was reduced annually from 2669 tons in 1999 to 916 tons in 2001 tons and eventually to 132.55 tons in 2010, also the ambient lead levels were measured during the period of 1999 through 2010, measurements showed that lead concentrations decreased dramatically from 1999 to 2010. The largest change was at industrial area where PM10 lead decreased from 33.7μg/m3 during winter, 1999 to 0.3μg/m3 during summer, 2010.
A completed preliminary analysis was done to evaluate the most contaminated site “Lead Smelter” site in terms of its potential to pose risks to people and the environment. During this assessment, soil and water samples were taken and analyzed for various contaminants and preliminary conclusions. High concentrations of lead and other hazardous metals in the soil—reaching a maximum value 78 percent render the site heavily polluted, which pose an extreme environmental hazard and serious health problems especially for children.
Remediation guidelines for lead smelters is provided and the health risk on the residents of the neighborhood is decreased
Dr. Zeinab Safar is Emeritus Professor of Mechanical Engineering Department at Cairo University; she had her B.S. degree from Cairo University, M.S. degree and Ph.D from University of Pittsburgh, USA. In addition to Cairo University Dr Safar worked in many universities as visiting professor such as University of California Berkeley, Aachen University and the American University in Cairo. She has more than 80 publications in the areas of Tribology, Energy, and Environment in International Journals and Conferences. Dr. Safar has received the Change Agent Award from ABI and the Community Research Prize from Cairo University. She is a member of the Board of the Electricity Holding Company and the National Committee of Women in Science and Technology in the Academy of Scientific Research.
Department of Materials Science, Indian Association for the Cultivation of Science, India
Increasing global demand for energy, coupled with cleaner environmental requirement, is one of the biggest challenge being faced today. Materials for energy storage, be it conventional or renewable, are subjected to intense research and development. In this talk, I shall start with an overview of the essential requirements for storage of renewable energies, from the point of view of a materials scientist. I shall then focus on some nanostructures, in particular carbon based nanostructures, that can be used for efficient storage of hydrogen and also as metal-free catalysts for low temperature fuel cells. First principles density functional based simulation prove extremely handy in designing such novel materials with desired combination of properties After presenting some case studies, I shall wrap up by arguing how materials scientists, who sometime might sound futuristic, can play a crucial role in building up a sustainable energy economy.
Faculty of Civil Engineering, Universiti Teknologi Malaysia, Malaysia
Conventional methods for constructing the pad footings required the used of plywood as formwork and reinforcement bar, thus both materials required the used of skilled workmanship in construction site. The main concern in conventional pad footing is wastage, this is because some of the materials such that plywood can no longer be used and will contribute to the additional construction cost. The purpose of this research is to investigate the structural behavior of prefabricated pad footing system using cold formed steel (CFS) lipped channel section where CFS were used as reinforcement bar and permanent formwork, by carrying out experimental tests. In addition, the experimental test results were validate with theoretical calculation and the economical aspect of CFS in pad footing system were compared with conventional pad footing throughout the steel area required. There were nine 3 full scale specimens for square pad footing with internal CFS is arranged parallel to the support have been tested. All samples are tested until failure using uniform axial compression tests. During the testing, all samples were put under increment of loads; maximum failure load, failure modes and displacement were observed and recorded. Experimental results were then compared to theoretical prediction using MSEN 1992(2010) Eurocode 2 part 1-1. The comparison shows good result between experimental and theoretical calculation. The use of CFS in ad footing seems more economic compared of using conventional methods of constructing the pad footing.
Keywords: Pad Footing; Cold Formed Steel Lipped Channel Section; Compression Resistance; Axial Compression Test.