Moustafa T.,Ezz Flat Steel |
Khalifa W.,Cairo University |
El-Koussy R.,Cairo University |
Abd El-Reheem N.,Cairo University
AES-ATEMA International Conference Series - Advances and Trends in Engineering Materials and their Applications | Year: 2015
Welding is highly recommended for splicing concrete reinforcing bars in all concrete structures. SMAW lap-weld and butt-weld joints made from Tempcore and hot-rolled reinforcing steel bars were studied. The work aimed at establishing the effective lap weld lengths and the proper metallurgical properties for the different joint types, bar sizes and preheating conditions. It was found that the hot-rolled bars gave lower acceptable lap length than the Tempcore bars. This was because of the higher amount of pearlite/bainite phases in weld area. In the other hand, the HAZ hardening resulted in the most pronounced changes in ductility of hot-rolled joints. Preheating the hot-rolled bars up to 200°C was insufficient to prevent the formation of HAZ hard phases. © 2015, Advanced Engineering Solutions (AES.COM).
Hekal E.E.,Ain Shams University |
Abo-El-Enein S.A.,Ain Shams University |
El-Korashy S.A.,Suez Canal University |
Megahed G.M.,Ezz Flat Steel |
El-Sayed T.M.,Ezz Flat Steel
Journal of Thermal Analysis and Calorimetry | Year: 2013
Electric arc furnace dust (EAFD) is termed as a hazardous waste due to its contamination with heavy metals. Inertization of such very fine dust can be occurred via stabilization and solidification process within the hydrated Portland cement matrix. In this paper, the effect of the addition of various ratios of EAFD on the properties of the hardened Portland cement paste was investigated. Compressive strength, chemically combine water and free lime contents were determined. In addition, phase composition using XRD; DTA analysis; as well as microstructure of the formed hydrates for some selected samples were investigated using SEM. The obtained results showed that the paste containing 1/mass% EAFD give the highest compressive strength values at most hydration ages, specially the later ages, compared to the neat Portland cement blank paste. Whileas, the pastes containing 3 and 5/mass% EAFD showed lower values of compressive strength compared to those of the blank paste. © Akadémiai Kiadó, Budapest, Hungary 2013.
Paul S.K.,Ezz Flat Steel |
Ahmed U.,Ezz Flat Steel |
Megahed G.M.,Ezz Flat Steel
Journal of Materials Engineering and Performance | Year: 2011
Low-carbon Al-killed hot rolled strips for direct forming, cold rolling, and galvanizing applications are produced from the similar chemistry at Ezz Flat Steel (EFS) through thin slab casting and rolling (TSCR) technology. The desired mechanical and microstructural properties in hot bands for different applications are achieved through control of hot rolling parameters, which in turn control the precipitation and growth of AlN. Nitrogen in solid solution strongly influences the yield strength (YS), ductility, strain aging index (SAI), and other formability properties of steel. The equilibrium solubility of AlN in austenite at different temperatures and its isothermal precipitation have been studied. To achieve the formability properties for direct forming, soluble nitrogen is fixed as AlN by coiling the strip at higher temperatures. For stringent cold forming, boron was added below the stoichiometric ratio with nitrogen, which improved the formability properties dramatically. The requirements of hot band for processing into cold rolled and annealed deep drawing sheets are high SAI and fine-grain microstructure. Higher finish rolling and low coiling temperatures are used to achieve these. Fully processed cold rolled sheets from these hot strips at customer's end have shown good formability properties. Coil break marks observed in some coils during uncoiling were found to be associated with yielding phenomenon. The spike height (difference between upper and lower yield stresses) and yield point elongation (YPE) were found to be the key material parameters for the break marks. Factors affecting these parameters have been studied and the coiling temperature optimized to overcome the problem. © 2010 ASM International.
Megahed G.M.,Ezz Flat Steel |
Fathy A.M.,Ezz Flat Steel |
Morsy M.A.,Ezz Flat Steel |
Abdelaziz E.A.,Ezz Flat Steel
Ironmaking and Steelmaking | Year: 2010
An important development of the modular chemical energy system layout, jet flowrate and jet length was implemented in electric arc furnace (EAF) at Ezz Flat Steel plant to reduce electrical energy consumption, avoid skull formation, reduce refractory consumption and improve foaming slag. This development was conducted in stages. The first stage included the implementation of new oxygen jets and a change to the jet distribution in upper shell perimeter water cooled panels. The second stage was to increase the length of the jets and increase the oxygen flowrate. The third stage, increased the jet length and the jet flowrate while the fourth stage, was the application period. The modifications led to a reduction in electrical power consumption of 64 kWh, reduction in refractory consumption of 48% and an increase in furnace productivity of 30%. © 2010 Maney Publishing.