الفهرس 
Introduction and Previous WorkOnly 14 pages are availabe for public view
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Abstract
Aluminium, tungsten and aluminium – tungsten ferritic stainless-steel alloys were developed and
produced using a 30 kg pilot plant induction furnace of medium frequency at the same conditions
to be applied in nuclear reactor shielding material. Precipitation hardening strengthening
technique with two different mechanisms M7C3, and Fe2W laves was studied in ferritic stainless
steel. The investigation was achieved by using optical and scanning electron microscope
observations to monitor either the chemical composition or the morphology of the
secondary phases. In addition, XRD was used to identify the change in constituent phases,
accompanying the heat treatment process. Mechanical properties and strain hardening character
of the steel were determined. It was found that morphology of W-base laves is coarse, and
nucleated at the high ferrite angle boundary. This provides much stability for ferrite boundaries,
enhancing the strength of the matrix with free effect on ductility. On contrary, M7C3
secondary phase has a significant deterioration effect on the ductility of ferrite stainless steel, in
opposite to its effect on enhancing yield and ultimate strength. Higher hardness, ultimate
strength, and ultimate tensile strength appeared in the developed alloys. Aluminium stainlesssteel elongation had lower values. The results of corrosion test showed that modified stainless
steel with aluminium and tungsten (FS11) has the highest corrosion resistance among all
investigated steels. Finally, total slow neutrons, neutrons > 10 keV, and slow neutrons of
aluminium-tungsten based ferritic stainless-steel alloys which carried out using 241Am-Be
neutron source as well as a wide range up to 1400 keV energies of gamma rays, which emitted
from Co-60, Cs-137 and Eu-152, were used by means of NaI (Tl) detector and studied using the
XCOM program. Results showed that all studied stainless-steel alloys own a converge values of
Abstract
XIII
neutron macroscopic cross sections (Σ, cm-1
). Moreover, there is no significant variation of the
value of mass attenuation coefficients (σ, cm2
/g) for the studied alloys. Good agreement between
both experimental and calculated results of mass attenuation coefficients was achieved. A new
composition for several nuclear applications such as, nuclear shielding applications were
achieved.
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Keywords:
Fusion and fission reactors, Nuclear reactor materials, Ferritic stainless steel, W,
Al and tungsten-aluminum stainless steel, Structural, Mechanical and Attenuation
properties, Neutrons, Gamma rays.