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The present investigation pertains to effect of different levels of modifiers (Na) in the Al-11.1Si hypo-eutectic alloy casting process. The investigation deals with the porosity analysis of the hypo-eutectic Al-Si alloy casting with varying master alloy, composition and holding time. The modifiers used for the investigation is sodium. Four levels of compositions addition of modifier as sodium is selected for the casting process which are 0.03%, 0.06%, 0.09%, &0.12%. The holding times selected for each composition are 10min, 20min and 30min respectively. The introduction sodium to an Al-Si alloy results in a complete transformation of Si particles, changing them from coarse plates to fine fibres, irrespective of the cooling conditions. The reduction in eutectic growth temperature due to sodium addition was consistently associated with the degree of modification, regardless of the initial microstructure coarseness.

Magnesium and its alloys are promising engineering materials with broad potential applications in the automotive, aerospace, and biomedical fields. These materials are prized for their lightweight properties, impressive specific strength, and biocompatibility. However, their practical use is often hindered by their low wear and corrosion resistance. Despite their excellent mechanical properties, the high strength-to-weight ratio of magnesium alloys necessitates surface protection for many applications. In this particular study, we employed the plasma spraying technique to enhance the low corrosion resistance of the AZ91D magnesium alloy. We conducted a wear analysis on nine coated samples, each with a thickness of 6mm, to assess their tribological performance. To evaluate the surface morphology and microstructure of the dual-phase treated samples, we employed scanning electron microscopy (SEM) and X-ray diffraction (XRD).

Magnesium alloys possess a unique combination of benefits stemming from their exceptional strength-to-weight ratio and reduced density. The aforementioned attributes render them notably attractive for utilization in automotive and aeronautical sectors. Furthermore, these alloys are gaining significant interest from the industry because of their outstanding dimensional stability, excellent ability to dampen vibrations, high recyclability, and good castability. They also exhibit superior stiffness, among other attributes. Nonetheless, magnesium and its alloys face several noteworthy challenges that limit their industrial utilization. These include low resistance to deformation over time, limited stability at high temperatures, restricted malleability, poor ductility, and inadequate resistance to corrosion. This study aims to investigate the phenomenon of stress corrosion cracking in magnesium alloy when exposed to potassium chromate. Addition of Ca showed better mechanical properties.

This study focuses on enhancing the corrosion resistance of AZ91D magnesium alloy, known for its impressive strength-to-weight ratio within the magnesium group. Despite its lightweight properties, the alloy's moderate corrosion and wear resistance have restricted its widespread use. To address this limitation, we explored the application of the Dow 17 process to enable hard anodizing of AZ91D magnesium alloy. Our primary objective is to investigate the impact of hard anodizing on AZ91D magnesium alloy and its potential to mitigate corrosion issues. Hard anodizing results in the formation of a robust oxide film on the alloy's surface. We posit that this oxide film can significantly reduce substrate corrosion, expanding the alloy's utility in various applications. To substantiate our claims, we conducted a comprehensive corrosion performance analysis of AZ91D magnesium alloy, with and without hard anodizing treatment.

Effect of Lanthanum addition on mechanical properties of LA93 along with its microstructural evolution has been analysed using optical microscopy, scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). The phases of this alloy were identified by X-ray diffraction (XRD). La addition has resulted in a reformed semi continuous structure with a decrease in grain volume along the boundary. The morphology shows the formation of Al2La and Al3La phase while the AlLi in LA93 has decreased. At 1.5 wt% La addition, the maximum grain refinement is obtained. In LA93+xLa, the Al2La and Al3La appear as a white long stripy phase and a white large blocky phase, respectively, and contribute to the increased strength of the alloy. There is a clear distribution of intermetallic compounds along the grain boundary of α-Mg and inside the matrix. The ultimate tensile strength increases by 60% to 112 MPa and hardness increases by 48% when the La content is 1.5 wt%.