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Electromagnetic welding, also referred to as magnetic pulse welding, is a solid-state welding method utilized for joining two distinct materials through high velocity impact. The direct fusion of stainless steel with titanium poses various difficulties owing to the absence of metallurgical compatibility and the occurrence of brittle intermetallic compounds such as FeTi and CrTi. To tackle these challenges, a sustainable, low heat input method like impact welding was applied to address the metallurgical compatibility of the two metals. In this study, a new technique involving aluminum foil, silver foil, and nitinol powder as intermediary materials was investigated to establish a fresh bimetallic structure between Ti-SS304L. Thorough analysis of microstructures, interface formations, and reactions was conducted using scanning electron microscopy and X-ray diffraction. The outcomes showcased successful prevention of intermetallic phase formation through the incorporation of these intermediary materials. Microhardness measurements indicated the absence of brittle FeTi and CrTi phases at the welding interface. Additionally, the weld interface was observed to be situated amid two intermetallic layers at the Ti-SS304L interface, ensuring resistance against corrosion. This inventive method not only averted the creation of harmful intermetallic compounds but also bolstered the overall strength and corrosion resilience of the joint between titanium and stainless steel. The micro hardness obtained at Ti-SS304L interface is 305 Hv and also improved 20% at interface of interlayer materials. [ABSTRACT FROM AUTHOR]

Welding is a suitable and better process to manufacture complex objects for aerospace, naval, and automotive structures. Service conditions and complexity in load acting force the manufactures to make joints between dissimilar materials. Thus, there is a need for efficient welding techniques to form sound joints and an understanding of imperfections and their effects. In this study an attempt has been made to study the joining feasibility of dissimilar aluminum alloys by two different welding techniques, namely, tungsten inert gas welding (TIG) and friction stir welding (FSW). Dissimilar AA5083-O and AA7075-T651 aluminum alloys successfully joined by considered welding techniques. Metallurgical and mechanical characteristics of fabricated weld joints are studied at different weld currents (80–120 amp) for TIG and various rotational speeds (800, 1000, 1100, 1200, and 1400 rpm) with constant traverse speed for FSW. Weld joints made by FSW exhibit superior tensile strength, whereas the joint line microhardness of TIG samples is higher than the FSW ones. [ABSTRACT FROM AUTHOR]

In this work, the silicon carbide (SiC) and titanium diboride (TiB2) reinforced as-cast Zn-Al-Cu alloy-based hybrid composites were produced with ultrasonic-assisted stir casting. The corrosion behavior of as-cast Zn-Al-Cu/TiB2/SiC hybrid composites with varying 0, 5, 10, and 15 weight percent of SiC + TiB2 particulates in Zn-Al-Cu matrix alloy was investigated in this study, The effect of additional reinforcements content on the corrosion behavior of hybrid composites with respect to Zn-Al-Cu alloy was investigated. The corrosion rate of hybrid composites was taken by using potentiodynamic polarization equipment (with 3.5 wt.% NaCl solution). The potentiodynamic polarization test findings showed that the hybrid composites' uniform and localized corrosion resistances were enhanced by the addition of dual reinforcements. As the weight fraction of the SiC/TiB2 reinforcement increases, weak microgalvanic cells that form between the constituent phases of the fabricated as-cast Zn-Al-Cu hybrid composites weaken, improving their resistance to uniform and localized corrosion. The results revealed that the corrosion rate values were reduced to 28.88% at 15% of reinforcement when compared to the base alloy. [ABSTRACT FROM AUTHOR]

The composite was made using the stir cast manufacturing method. Many parameters, like stirring speed, stirring time, ZrO2% reinforcement, and cast temperature, are evaluated in a Taguchi experimental design to see how they affected the composite properties. In terms of composite properties, ZrO2% reinforcement and the stir speed have the most significant impact. There were 25.02% gains in ultimate tensile strength and hardness, as well as a decrease in composite wear loss, when the optimal stir casting parameters were used compared to the initial stir casting settings. To get insight into the process and the qualities of the composite, the hot-pressing parameters were studied. Pressure, followed by temperature, is the most critical factor in determining the properties of composites. When a hot-pressing setting was determined to reduce the wear loss by a significant 39.3%, it was deemed perfect by the superranking concept. Under ideal conditions, hot-pressing procedures reduced wear loss by 40.8% while boosting ultimate tensile strength and hardness by 19.83% and 9.6%, respectively. The resulting microstructures and worn surface morphologies from stir casting and hot pressing show vastly different properties. [ABSTRACT FROM AUTHOR]

The microstructure and mechanical properties of an MMC based on AA 7075 and strengthened through silicon carbide (SiC) as well as boron carbide (B4C) elements were studied. The (SiC + B4C) combination was used in various weight percentages of 4, 8, 12, and 16% to create the hybrid composites utilizing the traditional stir casting procedure. XRD and SEM measurements were used to investigate the dispersion of the reinforced particles. For example, microhardness, impact strength, and ultimate tensile strength were measured on hybrid composites at room temperature. The density and porosity of the materials were also studied. The researchers found that increasing the weight percentage of the (SiC + B4C) mixture resulted in a small drop in % elongation. However, hybrid composites comprising 16% (SiC + B4C) weight reduction showed some decrease in hardness and tensile strength. Equated to unreinforced alloys, the hardness and tensile strength of hybrid composites rise by 8% and 21%, respectively. Reinforcement also resulted in a decrease in impact strength and density, as well as an increase in porosity. [ABSTRACT FROM AUTHOR]

This study investigates the dynamic responses of carbon nanotubes (CNT) reinforced composite sandwich shells with multi magnetorheological elastomer (MRE) core. The CNT reinforced composite skin layers are made by using hand layup technique. An experimental modal test has been carried for with and without CNT reinforced composite cylindrical shells under clamped free condition. The 3D finite element model is verified by comparing the obtained natural frequencies with experimental results. The numerical results indicate that the CNT reinforced composite multi‐MRE cylindrical sandwich shell greatly influences the natural frequencies compared with single‐MRE cylindrical sandwich shell. The effect of many parameters on the natural frequencies of the CNT reinforced composite multi‐MRE cylindrical sandwich shells is also discussed, including the weight percent of CNT, magnetic fields, and support conditions. [ABSTRACT FROM AUTHOR]