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Kamel, R., E. Najeeb, Y. A. Badr, M. A. Semary, and M. A. Hadhoud, "TWO-STAGE STRESS-DEPENDENT CREEP MECHANISM IN PLASTICIZED POLY(VINYL CHLORIDE) (PVC).", Journal of polymer science. Part A-1, Polymer chemistry, vol. 17, no. 12, pp. 4003-4010, 1979. AbstractWebsite
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Kashyout, A. B., M. Fathy, S. Gad, and B. A. A. Y. Badr, "Synthesis of nanostructure InxGal-xN bulk alloys and thin films for LED devices", Photonics, 2019.
Kassem, M. A., and R. M. Khafagy, "Thermal stability, crystallization kinetics and mechanical properties of Al81.8Ni9.2Co4.8Y3.1Zr1.1 amorphous alloy consolidated to a fully dense nanocrystalline matrix with some remaining amorphous phase", Journal of Alloys and Compounds, vol. 607, pp. 291 - 299, 2014. AbstractWebsite

Abstract High-strength nanocrystalline-embedded-alloy was successfully fabricated by the consolidation of melt-spun amorphous ribbons of Al81.8Ni9.2Co4.8Y3.1Zr1.1. The as-melt amorphous spun, the annealed and the fully dense nanocrystalline extruded specimens were investigated using XRD, HRTEM, SAED, \{EDX\} line mapping, microhardness, compression tests, \{SEM\} at fractured surfaces and the crystallization’s kinetics were determined from DSC. XRD, in good accordance with HRTEM, \{SAED\} and the associated \{EDX\} line mapping analysis, revealed the merely amorphous nature of the as-melt spun ribbons and confirmed bearing of nanocrystalline-embedded phases in the annealed and extruded specimens with the remaining of some amorphous phase. \{HRTEM\} and \{SAED\} revealed that annealing at 275 °C resulted in the formation of short-range ordered regions of fcc α-Al nanoparticles and intermetallic nanocrystalline-embedded grains of 5–10 nm that grown to 20–50 nm after extrusion. \{DSC\} showed that the as-melt spun ribbons crystallize at three stages in contrast to one late stage shown by the extruded sample. Crystallization kinetics of the as-spun ribbons yielded crystallization activation energy (Ec) of 143.4 and 36 kJ/mol for the first and second crystallization peaks respectively. The extruded specimen showed improved strength of 550 at a load of 50 g while the as-melt spun ribbons indicated lower hardness of 367 at a similar load. The ultimate compressive stress of the extruded specimen reached 800 MPa with 0.66% strain and Young’s modulus of 1.26 GPa. \{SEM\} micrographs of the fracture surface showed a transgranular failure with a dimpled surface reflecting the microplasticity of the final product. Improved mechanical properties and thermal stability of the nanocrystalline-embedded-specimen are due to the nanoparticle strengthening effect of the very hard and non-deformable nanosized α-aluminum and Al-based intermetallic nanograins that are densely formed during the annealing, extrusion and nano-indentation processes.

Kassem, M. A., and R. M. Khafagy, "Thermal stability, crystallization kinetics and mechanical properties of Al81.8Ni9.2Co4.8Y3.1Zr1.1 amorphous alloy consolidated to a fully dense nanocrystalline matrix with some remaining amorphous phase", Journal of Alloys and Compounds, vol. 607, pp. 291 - 299, 2014. AbstractWebsite

Abstract High-strength nanocrystalline-embedded-alloy was successfully fabricated by the consolidation of melt-spun amorphous ribbons of Al81.8Ni9.2Co4.8Y3.1Zr1.1. The as-melt amorphous spun, the annealed and the fully dense nanocrystalline extruded specimens were investigated using XRD, HRTEM, SAED, \{EDX\} line mapping, microhardness, compression tests, \{SEM\} at fractured surfaces and the crystallization’s kinetics were determined from DSC. XRD, in good accordance with HRTEM, \{SAED\} and the associated \{EDX\} line mapping analysis, revealed the merely amorphous nature of the as-melt spun ribbons and confirmed bearing of nanocrystalline-embedded phases in the annealed and extruded specimens with the remaining of some amorphous phase. \{HRTEM\} and \{SAED\} revealed that annealing at 275 °C resulted in the formation of short-range ordered regions of fcc α-Al nanoparticles and intermetallic nanocrystalline-embedded grains of 5–10 nm that grown to 20–50 nm after extrusion. \{DSC\} showed that the as-melt spun ribbons crystallize at three stages in contrast to one late stage shown by the extruded sample. Crystallization kinetics of the as-spun ribbons yielded crystallization activation energy (Ec) of 143.4 and 36 kJ/mol for the first and second crystallization peaks respectively. The extruded specimen showed improved strength of 550 at a load of 50 g while the as-melt spun ribbons indicated lower hardness of 367 at a similar load. The ultimate compressive stress of the extruded specimen reached 800 MPa with 0.66% strain and Young’s modulus of 1.26 GPa. \{SEM\} micrographs of the fracture surface showed a transgranular failure with a dimpled surface reflecting the microplasticity of the final product. Improved mechanical properties and thermal stability of the nanocrystalline-embedded-specimen are due to the nanoparticle strengthening effect of the very hard and non-deformable nanosized α-aluminum and Al-based intermetallic nanograins that are densely formed during the annealing, extrusion and nano-indentation processes.

Khafagy, R. M., and Y. A. Badr, "In situ FTIR spectroscopic study of the recently detected low-temperature-induced structural changes in isotactic polypropylene", Journal of Polymer Science, Part B: Polymer Physics, vol. 43, no. 20, pp. 2829-2842, 2005. AbstractWebsite
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Khalil, G. E., G. Abdel Fattah, M. Salali Shafik, and Y. A. Badr, "Comparison of CW laser performance of Nd:YAG and Nd:YLF under laser diode pumping", 3rd Workshop on Photonics and its Application at Egyptian Engineering Faculties and Institutes, pp. 123-140, 2002. Abstract
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Khames, G., A. A. Mona, M. H. Gihan, A. S. Sadik, and Y. Badr, "Application of laser microbeam cell surgery and Agrobacterium-mediated gene transformation systems in melon (Cucumis melo L)", Pakistan Journal of Biotechnology, vol. 6, no. 1-2, pp. 45-54, 2009. AbstractWebsite
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