Khaled Youssef

Prof. Khaled Youssef

orcid

Research Focus & Metrics

Academic Career Length

23Years (2004-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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9 December 2014 in Materials Research Letters
Verified
Journal Article
Open access
KYKhaled Youssef
Khaled Youssef
AZAlexander J. Zaddach
Alexander J. Zaddach
CNChangning Niu
Changning Niu
DIDouglas L. Irving
Douglas L. Irving
CKCarl C. Koch
Carl C. Koch
A low-density, nanocrystalline high-entropy alloy, Al20Li20Mg10Sc20Ti30 was produced by mechanical alloying. It formed a single-phase fcc structure during ball milling and transformed to single-phase hcp upon annealing. The alloy has an estimated strength-to-weight ratio that is significantly higher than other nanocrystalline alloys and is comparable to ceramics. High hardness is retained after annealing.

1 March 2005 in Acta Materialia
Verified
Journal Article
Closed access
SCS Cheng
S Cheng
EME Ma
E Ma
YWY Wang
Y Wang
LASZLO KECSKESLASZLO KECSKES
LASZLO KECSKES
KYKhaled Youssef
Khaled Youssef
KHK Han
K Han

1 January 2006 in Scripta Materialia
Verified
Journal Article
Closed access
KYKhaled Youssef
Khaled Youssef
RSR.O. Scattergood
R.O. Scattergood
KMK.L. Murty
K.L. Murty
CKC.C. Koch
C.C. Koch

22 August 2005 in Applied Physics Letters
Verified
Journal Article
Closed access
PDF file
KYKhaled Youssef
Khaled Youssef
RSRonald O. Scattergood
Ronald O. Scattergood
KMK. Linga Murty
K. Linga Murty
JHJoseph A. Horton
Joseph A. Horton
CKCarl. C. Koch
Carl. C. Koch
We have synthesized artifact-free bulk nanocrystalline copper samples with a narrow grain size distribution (mean grain size of 23nm ) that exhibited tensile yield strength about 11 times higher than that of conventional coarse-grained copper, while retaining a 14% uniform tensile elongation. In situ dynamic straining transmission electron microscope observations of the nanocrystalline copper are also reported, which showed individual dislocation motion and dislocation pile-ups. This suggests a dislocation-controlled deformation mechanism that allows for the high strain hardening observed. Trapped dislocations are observed in the individual nanograins.

1 August 2011 in Acta Materialia
Verified
Journal Article
Closed access
KYKhaled Youssef
Khaled Youssef
MSMiroslava Sakaliyska
Miroslava Sakaliyska
HBHamed Bahmanpour
Hamed Bahmanpour
RSRonald Scattergood
Ronald Scattergood
CKCarl Koch
Carl Koch

4 August 2004 in Applied Physics Letters
Verified
Journal Article
Closed access
PDF file
KYKhaled Youssef
Khaled Youssef
RSRonald O. Scattergood
Ronald O. Scattergood
KMK. Linga Murty
K. Linga Murty
CKCarl Koch
Carl Koch
We report a unique way of using mechanical milling/in situ consolidation at both liquid-nitrogen and room temperature to produce artifact-free nanocrystalline Cu(23nm) with a narrow grain size distribution. This nanocrystalline Cu exhibits an extraordinarily high yield strength (770MPa) , as predicted from a Hall–Petch extrapolation, along with good ductility (comparable with ∼30% uniform tensile elongation). Possible factors leading to this excellent optimization of strength and ductility are discussed.