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Defect Investigation of Plastically Deformed Al 5454 Wrought Alloy Using PADBS and Electrical Measurements M.
Abdel-Rahman Physics Department, Faculty of Science, El-Minia University, Egypt * e-mail : el_rahman@yahoo.com, ** e-mail : emadbadawi@yahoo.com Keywords: Positron annihilation Doppler broadening spectroscopy; electrical measurements; Al 5454 alloy; defect concentration; dislocation density Abstract Positron Annihilation Doppler Broadening Spectroscopy (PADPS) is a nondestructive technique used in materials science.
The chemical composition of Al 5454 alloy is shown in Table (1).
Table 1 The chemical composition of Al 5454 wrought alloy Element Cr Cu Ti Zn Si Fe Mn Mg Al Al 5454 0.05- 0.2 0.1 o.2 0.25 0.25 0.4 0.5-1 2.4-3 Balance Al 5454 Alloy has a very good resistance to atmospheric corrosion, very good weldability and good formability by pressing, drawing and roll-forming.
A sandwich configuration has been used to guide the positron into the Al 5454 samples.

Davydov et.al.: Mat.
Tregubova, M.Scheglov et al.: Mat.
Davydov et al.: Appl.
Zywietz, et.al.: Phys.
Cherenkov et.al.: Solid State Phenom.

It was found that the SS state is most likely realized in Fe-Al alloys for certain concentrations [6-8].
Assuming that the directions of quantization axes ej can be different depending on site, the Hamiltonian can be rewritten in the form: ( )22 ,, ,, 4 1 1 = jj j δjj δj Se∑ ∑ −++ + 
 U Uncct 
 H el σσ σ , (2) where Sj is a spin at site j, nel is a number of electrons per one site.
Then a minimum of the total energy ) ( 1 ) 4 (==),( 2 2 0 0 BBAA F el SS nn 
 n MUH E QkQkkk k Q +++ ++ 〉〈 ∑ εε ψ ε (8) over the Q wave vector and the ψ angle should be found.
Belk et al: Phys.
Reissner et al: Phys.

Near-interface-traps (NITs), reported by Afanasev et al.
Recently, El-Sayed et al. suggested wide-angle O-Si-O bonds as defect configuration, that act as electron traps and have a similar energy as the measure trap level.
Identification of Traps In 1997, Afanasev et al. measured near-interface-traps (NITs), that could be emptied by an optical energy of 2.77(5) eV [10].
A recent theoretical study by El-Sayed et al. reported on a strongly localized electron, which appears in a disordered oxide due to a wide O-Si-O angle [11] and has a similar energy value of about 3.17 eV.
El-Sayed, Physical Review B 89.12 (2014)

On the other hand, numerous investigations, so far, have explored the role of magnesium in Al-Si and Al-Si-Cu alloys [6-10].
The quality index (Q=UTS+150 log %El) has also been calculated for the investigated alloys to compare the combination of tensile properties. 2.
Modification and grain refinement of the alloys were achieved by adding 0.2 wt.% Al-10Si and 5 wt.% Al-5Ti-1B to the molten metal.
Effect of Mg content and artificial aging on the as-cast and heat treated tensile properties of the alloys (a) YS (b) UTS (c) % El (d) Quality index.
The effect of Mg concentration on the percent elongation to failure (%El) is depicted in Fig. 4c.

Park, et al.
Yu, et al.
Forrest, et al.
Yu, et al.
Shi, et al.

Table 1 Chemical composition of three types of HNS /wt% C Cr Mn Mo Si P Al Ni O N Fe HNS-77 0.057 19.15 18.83 2.25 0.38 ≤0.03 <0.03 — 0.0052 0.77 Bal.
The results of YS, UTS and El present the same regularity in HNS-77 and HNS-96 except HNS-110.
The plots of YS, UTS and El decrease monotonously in aged HNS-110 as shown in Fig. 6 (c).
Katada et al., ISIJ Int., Vol. 42 (2002), p. 1391
Jiang et al., Adv.

Southin [4], Abd El-Azim and coworkers [12], and Appendino and coworkers [13] assumed that vibration acceleration/force is the determining parameter.
Properties of 1040CR steel mold and for Al-12.6%Si can be found elsewhere [19, 20].
Abd El-Azim, A.
El-Sheikh, M.
T El-Khair: Mat.

Energy Efficient Technology for Al–Cu–Mn–Zr Sheet Alloys N.A.
Experimental Four experimental alloys of the Al-Cu-Mn-Zr system (Table 1) were prepared in an electric furnace in graphite-chamotte crucibles using 99.99% pure Al, 99.9% pure Cu and master alloys (Al10% Mn, and Al-10% Zr).
Alloy 2 has higher YS and El values in comparison with annealed Alloy 4.
Tensile properties of Al-Cu-Mn-Zr sheets.
Smola, et al., Effect of cold rolling on precipitation processes in Al–Mn–Sc–Zr alloy, Mat.

The yield stress at 0.2 % plastic strain (YS), the ultimate tensile stress (UTS), the uniform elongation (UEL) and the elongation to failure (EL) are compared.
The mechanical properties of the reference material are as follows: YS=370 MPa, UTS=510 MPa, UEL=19.0 % and EL=20.8 %.
This condition shows an increase of YS and UTS of ~35 % and ~10 % respectively, combined with a reasonable EL of 7.8 %.
Accordingly a maximum EL of 13 % is reached after aging for only 15 min at 170°C.
ECA-processing at 180°C yields an increase of YS and UTS of ~40 % and ~15 % respectively, combined with a remarkably EL of 11.6 %.