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Arab Journal of Nuclear Science and Applications, 46(2), (107-114) 2013
In many industrial applications, the mechanical properties of Al–Mg alloys are required to be
further improved. One of the methods used to improve the mechanical properties of Al–Mg alloys is
exposuring the alloy to radiation. The primary cause of radiation damage in metals is the displacement
of atoms and electrons (13) . The radiation damage is actually composed of several distinct processes (14) .
These processes and their order of occurrence are as follows:
1. The interaction of an energetic incident particle with the lattice atom.
2. The transfer of kinetic energy to the lattice atom giving birth to a primary knock-on atom (PKA).
3. The displacement of the atom from its lattice site.
4. The passage of the displaced atom through the lattice and the accompanying creation of additional
knock-on atoms.
5. The production of a displacement cascade (collection of point defects created by the PKA).
The radiation damage is concluded when the PKA comes to rest in the lattice as an interstitial.
The result of a radiation damage event is the creation of a collection of point defects (vacancies and
interstitials) and clusters of these defects in the crystal lattice. Several investigations were carried out
to interpret the effect of γ-irradiation on the mechanical and electrical properties of metals and alloys
(15-17) . The results mostly showed that γ-irradiation effect causes increase of the strengthening
parameters and electrical resistivity of the irradiated materials. This was attributed to the irradiationinduced
point defects created in the irradiated materials.
One of the most essential phenomena in deformed irradiated metals or alloys is the workhardening.
The effect of deformation temperature on the work-hardening characteristics of the
irradiated Al based alloys was found to return backs the initial values of the strengthening parameters
(15) . This was attributed to the annihilation of the irradiated defects at their sinks at temperatures where
the defects become appreciably mobile (18) .
The present work is devoted to get an insight and provide some additional information about the
effect of γ-irradiation and the reverse effect of the deformation temperature on the work-hardening
parameters of Al-5356 alloy.
(i) Sample Preparation
EXPERIMENTAL PROCEDURES
This study has been carried out on commercial Al-5356 alloy supplied from Alumisr factory-
Helwan-Cairo-Egypt in the form of rod of 3mm in diameter. The chemical compositions of the alloy
under investigation are given in Table (1). The rods were cold drawn in steps into wires 0.6 mm in
diameter for stress-strain measurements. A part of the alloy was rolled into sheet of 0.3mm in
thickness and 5mm width for microstructure investigation.
Table (1): The chemical compositions of the Al-5356 solder alloy
Al Mg Fe Cu Si Mn Cr Zn Ti Be
93.5-94.5 4.5-5.5 0.4 0.1 0.25 0.05-0.2 0.05-0.2 0.1 0.06-0.2 0.0008
(ii) Heat Treatment and Irradiation Techniques
Samples in the form of sheet (5 x 5 x 0.3 mm) and wires (50 mm in length) were annealed for
5h at 773K in the solid solution region using a thermo regulated furnace. The temperature inside the
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