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This article discusses the origin and exhibition of the exchange bias (EB) phenomenon and magnetic memory effect in a variety of time (t) and temperature (T) dependent protocols in nanocrystalline CoSb2O4 (CSO). The traditional hydrothermal technique was followed in the preparation of cuboid shaped nanoparticles. The as-synthesized sample was characterized well via powder X-ray diffraction (PXRD) and transmission electron microscopy (TEM) studies revealing crystallite and particle sizes of ∼51 and ∼96 nm, respectively. Thermal variation of magnetization [M(T)] suggests creation of a canted antiferromagnetic (AFM) ground state with multiple magnetic transitions around 79, 50 and 11 K. Sizable orbital moment contribution has been validated from the mismatch between the experimental value and the theoretical estimation of the Curie–Weiss moment. Cooling field induced metastability below the first order magnetic transition and the explicit signature of the magneto-caloric-effect in terms of the change in entropy are two noteworthy features in this system. Below the ordering temperature, a substantial amount of EB (with EB field (HE) = 800 Oe at 3 K with a 40 kOe cooling field) has been demonstrated through the shift in the magnetic hysteresis (M−H) loop when cooled in an external magnetic field. Exchange interaction originates due to the cumulative effect of disorder and competing interactions because of the coexistence of more than one type of spin order. Creation of a super-spin-glass (SSG) like state due to the finite size effect and a strong dipolar interaction in the nanoparticle assembly manifest the memory effect in M(T) in field-cooled (FC) and zero-field-cooled (ZFC) protocols along with isothermal remanent magnetization (IRM) mechanisms. [ABSTRACT FROM AUTHOR]

This investigation involved the development and characterization (microstructure, mechanical properties, and dry sliding wear characteristics) of Al-Mg2Si composites for automobile applications. Consequently, the performance analysis of the Al-Mg2Si composites was conducted considering motorcycle disk brake rotor application. The digital logic method (DLM), a material selection process, was employed to compare the performance of Al-Mg2Si composites with traditional rotor materials, cast iron, and stainless steel. The motorcycle disk brake operation was simulated with steel and Al-20wt.% Mg2Si composite rotor to establish the findings of performance analysis. The DLM analysis revealed that the Al-20wt.% Mg2Si composite had a technical performance index of 73.65, while steel had a technical performance index of 78.10. Additionally, the energy efficiency index (EEI) for the composite and steel stood at 31.79 and 100, respectively. Furthermore, the composite exhibited much lower CO2 and CO emissions compared to steel, with values of 0.087 and 0.0026 g/km versus 0.276 and 0.0082 g/km, respectively. The simulation results indicated that both the stainless steel and the Al-20Mg2Si composite rotor exhibited structural suitability. In the Al-20Mg2Si composite rotor, the induced temperature ranged from 35.4 to 60.3 °C, while the heat flux ranged from 1.462 × 103 to 3.64 × 105 W/m2. On the other hand, the stainless steel rotor experienced induced temperature ranging from 41.55 to 87.4 °C, and heat flux ranging from 4.0 × 102 to 1.64 × 105 W/m2. The composite rotor demonstrated a lower induced temperature and higher heat flux, which in turn reduced the probability of both direct and indirect thermal damage and improved structural integrity. [ABSTRACT FROM AUTHOR]

This study investigates the wear characteristics of Al–25Mg2Si composite synthesized via gravity casting. The research aims to understand the influence of applied load, test temperature, contact condition (dry and lubrication), and sliding distance on wear characteristics. Results show that higher loads and temperatures lead to increased wear loss and coefficient of friction. The worn surface morphology for higher loads and temperature shows deeper scratches and grooves, indicating severity in wear. The debris size and volume increase with an increase in load and temperature. The dominant mechanism is abrasive, adhesive, and oxidative for both the room‐ and high‐temperature dry sliding conditions. However adhesive and oxidative wear increase with the increase in test temperature. Abrasive wear is the only wear mechanism present during the lubricating sliding condition. Wear transition is noticed during the wear map analysis subjected to load, temperature, and sliding distance. In the case of room‐temperature test, severe–moderate–mild wear transition occurs with the increase in sliding distance and mild–moderate–severe wear transition occurs with the increase in test temperature and applied load. The roughness of the worn surface increases with an increase in applied load and temperature and the use of lubricant hugely reduces the surface roughness. [ABSTRACT FROM AUTHOR]

This study aims to optimize the process parameters of wire arc additive manufacturing for ER70S6 steel and to build a machine‐learning (ML) model to predict the properties of deposited specimens. Process parameters such as current, voltage, and travel speed are optimized considering other process parameters constant (gas flow rate, contact tip to the work distance, and preheat). The optimization is made using the response surface method and validated the properties by experimentation, including tensile testing and metallography. A support vector regression (SVR) ML model is implemented to predict the material's properties to substantiate the outcomes' values in every possible combination for the given parameters. In the study's findings, a significant enhancement is revealed in specimen quality, marked by reduced irregularities and porosity, and a remarkable increase in ultimate tensile strength up to 40%, validated through the SVR model. In this study, a valuable path that can be extended to predict properties of other material systems is sketched. [ABSTRACT FROM AUTHOR]

This study utilised the gravity casting method to modify hypoeutectic Al-7.6Si alloys with Zr at varying weight percentages (0.1%, 0.2%, and 0.3%). The unmodified alloy typically consists of a needle or platelike eutectic silicon within the dendritic α-Al phase. The addition of Zr increases the liquidus temperature of the alloy and results in the formation of ZrSi and ZrSi2 compounds, which act as nucleation sites for both the eutectic Si and α-Al grains. As a result, the needle or platelike eutectic silicon transforms into a fibrous structurewith amore uniform distribution, and the α-Al phase becomes finer and globular. These microstructural changes lead to improved bulk hardness, ductility, and mechanical properties of the alloy. [ABSTRACT FROM AUTHOR]