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AA6082 alloys play a significant role in advancing sustainable development goals (SDGs) by contributing to environmental sustainability, economic growth, and social well-being. These alloys are highly recyclable and align with SDG 12 by promoting resource efficiency and reducing waste. Their application in lightweight vehicles and improving energy efficiency in construction supports SDG 9 and SDG 11, as they help reduce carbon emissions and enhance the sustainability of urban environments. While AA6082 alloys offer significant advantages, their use has limitations that can hinder their industrial applications. One key challenge is their lower formability, particularly at room temperature. Elevated-temperature deformation is frequently employed to enhance the formability of these alloys and address their limitations. Thus, a deep understanding of the constitutive analysis of these alloys under a wide range of T and ε ˙ is essential for manufacturing sound components from these alloys. Thus, this study aims to propose a new modification for the JC model (PJCM) and compare its reliability to predict the warm/hot flow behavior of AA6082 alloys with that of the original JC model (OJCM) and the modified JC model (LMJCM). By comparing the experimental results with these model results and confirming the determining correlation coefficient (R), average absolute relative error (AARE), and root mean square error (RMSE) values, it is concluded that the stresses predicted by the PMJCM closely match the experimental stresses of the LMJCM and OJCM because of the interaction between ε ˙ , ε , and T , which might be a reason for the complex nonlinear behavior of AA6082 alloys during hot deformation. [ABSTRACT FROM AUTHOR]

A promising method for additive manufacturing that makes it possible to produce intricate and personalized parts is selective laser melting (SLM). However, the mechanical properties of as-corroded SLM parts are still areas of concern. This research investigates the mechanical behavior of SLM parts that are exposed to a saline environment containing a 3.5% NaCl solution for varying lengths of time. The exposure times chosen for this study were 10 days, 20 days, and 30 days. The results reveal that the tensile strength of the parts is significantly affected by the duration of exposure. Additionally, the study also examined the influence of porosity on the corrosion behavior of the parts. The analysis included studying the mass loss of the parts over time, and a regression analysis was conducted to analyze the relationship between exposure time and mass loss. In addition, the utilization of scanning electron microscopy (SEM) and X-ray photo spectroscopy (XPS) techniques yielded valuable insights into the fundamental mechanisms accountable for the observed corrosion and mechanical behavior. It was found that the presence of corrosion products (i.e., oxide layer) and pitting contributed to the degradation of the SLM parts in the saline environment. This research emphasizes the importance of considering part thickness in the design of SLM components for corrosive environments and provides insights for enhancing their performance and durability. [ABSTRACT FROM AUTHOR]

This study aims to examine the factors affecting employee performance in textile mills across Karachi, Pakistan. Employing a quantitative, cross-sectional approach, the study used convenience sampling to collect data from employees across various textile mills. Data collection was facilitated using published scales from different researchers and conducted via Google Forms. Analysis was performed using SPSS version 17. The study identified that creativity, challenge stressors, hindrance stressors, transformational leadership, organizational innovation, and career development significantly influence employee performance. Creativity and career development emerged as the most influential factors, significantly enhancing employee performance, followed by organizational innovation, challenge stressors, and transformational leadership. Hindrance stressors, while negatively impacting performance, showed a less significant effect than expected. These findings provide valuable insights for managers in the textile industry and other sectors. By fostering creativity, promoting career development, and implementing transformational leadership and organizational innovation, managers can enhance employee and organizational performance. Additionally, recognizing and mitigating the impact of hindrance stressors is crucial for maintaining a productive work environment. This study contributes unique insights into the dynamics of employee performance within the context of Karachi's textile industry, a sector that has not been extensively explored in existing literature. It offers a comprehensive understanding of various factors that influence employee performance in this specific industrial setting, adding valuable knowledge to the field of organizational behavior and management. If employees of an organization perform well, the organization performs well. If the organization of a country performs well, the country performs well. [ABSTRACT FROM AUTHOR]

In the contemporary banking sector, green employee engagement has ascended as a critical driver of sustainability, drawing significant attention from business researchers worldwide. This research delves into the influential role of green leader emotional intelligence on green employee engagement, particularly within Karachi's banking milieu. Furthermore, it explores the mediating effects of green employee behavior and green organizational citizenship behavior in this dynamic relationship. Employing a convenience sampling strategy, data were amassed from 387 banking professionals in Karachi, Pakistan, providing a comprehensive insight into the sector's eco-conscious practices. Analytical procedures were conducted using SmartPLS 3.0, ensuring rigorous data interpretation and hypothesis testing. The findings underscore the pivotal role of leaders' emotional intelligence in fostering an environment conducive to green work engagement. Notably, the results reveal that green employee behavior and green organizational citizenship behavior significantly mediate the relationship between green leader emotional intelligence and green work engagement. These mediators bridge the gap, highlighting the importance of individual and collective actions in promoting an eco-friendly work ethos. This study contributes to the burgeoning literature on green human resource management, emphasizing the necessity of emotionally intelligent leadership in catalyzing sustainable employee practices. It advocates for a paradigm shift in leadership strategies, urging the adoption of green initiatives that resonate on an emotional level, thereby enhancing employee engagement and propelling the banking sector toward sustainable horizons. [ABSTRACT FROM AUTHOR]

The electronic characteristics, surface topography, and surface roughness of a Ti-3Cu alloy were investigated in phosphate buffered saline (PBS) containing bovine serum albumin (BSA) at 37 °C and pH 7.4 ± 0.2 by Mott-Schottky analysis (MSA) and atomic force microscopy (AFM). The n-type oxide layer was produced on the Ti-3Cu alloy surface due to the formation of oxygen-deficient TiO2-x barrier layer with interstitial copper as C u i +. As the serum-protein concentration increased from 1 g/L to 6 g/L in the phosphate buffered saline, the donor densities (ND) of the semiconducting oxide layer decreased. The accumulation of serum protein observed by atomic force microscopy became the driving force in the restructuring of the oxide film via chemisorption and caused a reduction in the donor densities. The change in the magnitude of the nano-roughness suggested chemisorption which is beneficial for the osseointegration of Ti-3Cu implants. [ABSTRACT FROM AUTHOR]

Foreign body reactions to the wear debris and corrosion products from the implants, and bacterial infections are the main factors leading to the implant failures. In order to resolve these problems, the antibacterial TiN/Cu nanocomposite coatings with various N2 partial pressures were deposited on 304 stainless steels (SS) using an arc ion plating (AIP) system, named TiN/Cu-x (x = 0.5, 1.0, 1.5 Pa). The results of X-ray diffraction analysis, energy-dispersive X-ray spectroscopy, and scanning electron microscopy showed that the N2 partial pressures determined the Cu contents, surface defects, and crystallite sizes of TiN/Cu nanocomposite coatings, which further influenced the comprehensive abilities. And the hardness and wear resistances of TiN/Cu coatings were enhanced with increase of the crystallite sizes. Under the co-actions of surface defects, crystallite sizes, and Cu content, TiN/Cu-1.0 and TiN/Cu-1.5 coatings possessed excellent corrosion resistance. Besides, the biological tests proved that all the TiN/Cu coatings showed no cytotoxicity with strong antibacterial ability. Among them, TiN/Cu-1.5 coating significantly promoted the cell proliferation, which is expected to be a novel antibacterial, corrosion-resistant, and wear-resistant coating on the surfaces of medical implants. [ABSTRACT FROM AUTHOR]

Mg-Zn-Ca metal glass shows good promising applications in biomaterials. MAO coating and Ca-P coating was applied on Mg69Zn27Ca4 metal glass in order to improve the alloy biodegradation resistance and biocompatibility. Microstructure observation, electrochemical experiment, immersion experiment and cell cytotoxicity experiment (MG63 cells) were carried out. The result revealed that Ca-P coating exhibited better degradation resistance than MAO coating due to its relatively thick and uniform structure. The cell cytotoxicity showed both coatings showed better bioactivity than the uncoated Mg69Zn27Ca4 metal glass. Moreover, Ca-P-coated samples had better bioactivity than those of MAO coated. Therefore, Ca-P coating improved not only the degradation resistance but also the bioactivity of Mg69Zn27Ca4 metal glass. Ca-P coating has a good promising application on Mg69Zn27Ca4 metal glass. [ABSTRACT FROM AUTHOR]

The research work focused on microstructural changes that occurred in DIN 42CrMo4 alloy during the induction hardening process with the emphasis on its corrosion and microhardness variations. In this strategy, experiments were performed on the gradually increasing values of induction heating power and time to observe the response of the studied alloy. The optical and scanning electron microscopy was used to examine the microstructures of the processed alloy. Mechanical performance of the induction hardened alloy was characterized using microhardness examination. It was found that the percentage of martensite phase fraction increased with induction heating powers i.e., of 10, 14, 18, and 22 kW. Similar trend was observed for extended induction heating time from 3 to 9 s. A characteristic transformation in martensitic morphology was also observed due to change in processing parameters, which created a significant effect on the corrosion performance and hardness value of the studied alloy. Hardness of the alloy progressively increases with the rise of induction heating power and time and stabilizes at higher input values of induction parameters due to complete execution of martensitic structure. On the characterization of the electrochemical properties, the study revealed that martensitic morphology played dramatic role in the corrosion performance of the alloy. it was found that lath martensitic structure offered greater corrosion resistance compared to coarse martensite with a trivial change in hardness value. Thus, utilization of proper induction parameters needs to be applied for the properties to be optimum. [ABSTRACT FROM AUTHOR]

To improve the oxidation resistance of carbon/carbon composites at high temperatures (>1770 K), they were coated with MoSi2-Si3N4/SiC. The slurry and pack cementation methods were adopted to deposit the inner SiC layer and outer MoSi2-Si3N4 layer. The phase composition, microstructure, and elemental distributions in the coating were analyzed using SEM, XRD, EDS, and Raman spectroscopy. Oxidation tests show that the deposited multi-layer coating can protect the carbon/carbon matrix from oxidation at high temperatures (>1770 K) for 150h and that the coating can withstand 40 thermal cycles between 1773 and 300 K. It is observed that Si3N4 assists in the formation of a dense SiO2 layer at a high temperature, which plays a vital role in increasing the thermal cyclic and oxidation resistance of the coating itself. The weight loss of coated carbon/carbon composite is attributed to the formation of micro-cracks and diffusion of SiO2, MoO3, and N2 out of the material at high temperatures. [ABSTRACT FROM AUTHOR]

The inherent low strength of zinc (Zn) alloys limits their application, and aging treatment is a method that can be used to improve the properties of Zn alloys significantly. In this work, the effects of aging temperature on microstructure, mechanical properties, and corrosion resistance of the as‐rolled Zn‐3Al‐1Cu alloy are studied. The results show that the mechanical properties and corrosion resistance of the alloy can be significantly improved by tuning the aging temperature. Through aging treatment, the grain size of the second phase grows and more of the second phase is precipitated, which improves the mechanical properties and plasticity of the as‐rolled Zn‐3Al‐1Cu alloy. The tensile and yield strengths of the as‐rolled Zn‐3Al‐1Cu alloy aged at 80 °C are the highest, which are 206.11 ± 1.63 and 177.57 ± 1.70 MPa, respectively. Conversely, the alloy aged at 160 °C displays the best plasticity, where its elongation reaches 25.66 ± 0.49%. In addition, aging at 160 °C leads to the best corrosion resistance, reaching a corrosion rate obtained by the electrochemical test of 0.0016 mm year−1. [ABSTRACT FROM AUTHOR]

Highlights from the article: Summary: In the present study aluminium silicon carbide (Al/SiC) composites were prepared by Keywords: Powder Metallurgy; Metal Matrix Composite (MMC); Aluminium (Al); Silicon Carbide (SiC); Cast aluminium silicon carbide metal matrix Silicon Carbide (SiC), Powder Metallurgy, Metal Matrix Composite (MMC), Aluminium (Al), Scanning Electron Microscope (SEM).