Search

Current filters:

Current filters:

Author

Subject

Date issued

Has File(s)

Search Results

Results 1-3 of 3 (Search time: 0.001 seconds).
  • <<
  • 1
  • >>
    • Analysis of the As-Cast Microstructure and Properties of the Ni-Based Superalloy MAR-M247® Produced Via Directional Solidification
    Authors: Rakoczy, Łukasz; Grudzień-Rakoczy, Małgorzata; Cygan, Rafał;  Advisor: -;  Co-Author: - (2023)

    The presented research investigates MAR-M247® Ni-based superalloy castings produced via directional solidification at various mold preheating temperatures (1510, 1566 °C) and withdrawal rates (3.4, 5.0 mm/min). Casting analyses were carried out via thermodynamic simulations, differential scanning calorimetry (DSC), X-ray diffraction (XRD), light microscopy (LM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), scanning transmission electron microscopy (STEM), and tensile testing. On DSC curve, four effects have been registered during cooling: liquidus (1337 °C), formation of eutectic γ − γ′ (1315 °C), precipitation of Ni7(Hf, Zr)2 (1244 °C), and M5B3 borides (1201 °C). The castings’ primary and secondary dendrite arm spacing decreases with increasing w...
    • Effect of Sn Concentration on the Structural and Thermal Properties of SnxSb20Se80−x Glasses
    Authors: Khalifa, Zaki S.; Mohamed, S. H.;  Advisor: -;  Co-Author: - (2023)

    SnxSb20Se80−x bulk glasses were prepared using the well-known melt quenching technique, where x was taken as 7.5 at.%, 9.5 at.%, 11.5 at.% and 13 at.%. X-ray diffraction (XRD) and differential scanning calorimetery (DSC) were used to monitor the crystallinity and transition temperatures, respectively. XRD examinations showed that the 7.5 at.% and 9.5 at.% compositions were purely amorphous, while the other two compositions exhibited a crystalline structure. DSC thermograms demonstrated that 7.5 at.% and 9.5 at.% alloys had a single crystallization peak, whereas for the 11.5 at.% and 13 at.% alloys, two exothermic peaks and three peaks appeared.
    • Efficiency enhancement and chrono-photoelectron generation in dye-sensitized solar cells based on spin-coated TiO2 nanoparticle multilayer photoanodes and a ternary iodide gel polymer electrolyte
    Authors: Bandara, T. M. W. J.; Gunathilake, S. M. S.; Nishshanke, G. B. M. M. M.;  Advisor: -;  Co-Author: - (2023)

    he effect of the thickness of a multilayer TiO2 photoanode on the performance of a dye-sensitized solar cell (DSC) made with a polyethylene oxide-based gel polymer electrolyte containing ternary iodides and performance enhancer 4-tert-butylpyridine is studied. Multilayer photoanodes consisting of up to seven layers of TiO2 nano-particles (13 nm and 21 nm) are prepared by spin coating of successive layers. XRD results confirm the predominant presence of the anatase phase of TiO2 in the multilayer structure after sintering. The SEM images reveal the formation of a single TiO2 film upon sintering due to merging of individually deposited layers. The photocurrent density (JSC) and the efficiency increase with the number of TiO2 layers exhibiting the maximum efficiency and JSC of 5.5% and...