Showing 2 results for Optimization.
Asaad Eqal, Haidar Akram,
Volume 21, Issue 0 (3-2024)
Abstract
The influence of different heat treatment parameters, namely solutionizing and artificial
aging conditions, on the microstructure, mechanical hardness, and corrosion resistance of Al-
12Si-Cu alloy are systematically explored in this work. Solution treatment was performed at
two temperatures (500°C and 530°C) and two durations (0.5 and 3 hours), and artificial aging
was made at two temperatures (180°C and 310°C) over two durations (2 and 5 hours).
Optical microscopy also showed interesting microstructural changes with fine grain
refinement and enhanced spheroidization of the coarse eutectic Si phase and a more uniform
distribution of primary intermetallic grains. These structural adjustments were identified as
direct determinants of properties of the material. Maximum microhardness (155 HV) was
achieved at the temperatures of 500°C/3 h solutionizing and 180°C for 5 h aging (S3), which
was ascribed to successful solid solution strengthening and fine precipitation hardening. In
contrast, the lowest hardness (54 HV) was obtained at the values 530°C/3 h + 310°C/5 h (S8),
showing the harmful impact of over-aging at higher temperatures. Analysis of
electrochemical corrosion detected a significant correlation between the corrosion resistance
and treated microstructure, where conditions favoring microstructural refinement resulted in a
decrease in corrosion current density. A Design of Experiments (DOE) method by way of the
Taguchi L8 orthogonal array was used to find out how each parameter contributed relative to
the other variable. The analysis revealed that, whilst the aging temperature was the most
influential factor to the microhardness, the solution time was the controlling factor on the
surface roughness. The results demonstrate a robust determination of the main processing
windows which are known to be crucial to enhance particular properties and verify the
tremendous feasibility of temperature control in heat treatment process optimization in
engineering the necessary trade-off between mechanical strength and corrosion performance
in Al-12Si-Cu alloys.
Muhammad Shahzad Sadiq, Muhammad Imran, Abdur Rafai, Muhammad Rizwan,
Volume 21, Issue 2 (6-2024)
Abstract
With increasing energy demand and depletion of fossil fuel resources, it is pertinent to explore the renewable and eco-friendly energy resource to meet global energy demand. Recently, perovskite solar cells (PSCs) have emerged as plausible candidates in the field of photovoltaics and considered as potential contender of silicon solar cells in the photovoltaic market owing to their superior optoelectronic properties, low-cost and high absorption coefficients. Despite intensive research, PSCs still suffer from efficiency, stability, and reproducibility issues. To address the concern, the charge transport material (CTM) particularly the electron transport materials (ETM) can play significant role in the development of efficient and stable perovskite devices. In the proposed research, we synthesized GO-Ag-TiO2 ternary nanocomposite by facile hydrothermal approach as a potential electron transport layer (ETL) in a regular planar configuration-based PSC. The as synthesized sample was examined for morphological, structural, and optical properties using XRD, and UV-Vis spectroscopic techniques. XRD analysis confirmed the high crystallinity of prepared sample with no peak of impurity. The optimized GO-Ag-TiO2 ETL exhibited superior PCE of 8.72% with Jsc of 14.98 mA.cm-2 ,Voc of 0.99 V, and a fill factor of 58.83%. Furthermore, the efficiency enhancement in comparison with reference device is observed which confirms the potential role of doped materials in enhancing photovoltaic performance by facilitating efficient charge transport and reduced recombination. Our research suggests a facile route to synthesize a low-cost ETM beneficial for the commercialization of future perovskite devices.
