Journal Article

Enhancing tribo-mechanical, microstructural morphology, and corrosion performance of AZ91D-magnesium composites through the synergistic reinforcements of silicon nitride and waste glass powder

Ismail, Emad A. A., Khan, M. Ijaz, Sharma, Shubham, Dwivedi, Shashi Prakash, Kumar, Abhinav, Awwad, Fuad A.

2024

Overview

The present investigation has employed recycled waste glass powder (WGP) and silicon nitride (Si 3 N 4 ) as reinforcing-agents within AZ91D-matrix composites. The composites were fabricated by employing the vacuum stir casting technique to mitigate the effects of oxidation and to ensure homogeneity, uniformity, and superior wettability among the AZ91D-matrix and reinforcements. A microscopic study provided confirmation of a uniform dispersion of WGP and Si 3 N 4 particles throughout the AZ91D-matrix. The tensile strength of the AZ91D/WGP/Si 3 N 4 composites rise with the inclusion of WGP particulates by up to 1.5 percent in AZ91D/7.5% Si 3 N 4 . However, the tensile strength of the AZ91D/9%Si 3 N 4 composite have showed maximum value as compared to other chosen formulations/combinations in the current investigation. The tensile strength of AZ91D/1.5% WGP/7.5% Si 3 N 4 composites has strengthened up to 12.13 percent with the comparison of base alloy AZ91D-matrix. In A1 formulated composite, the amount of WGP particulate has enhanced the hardness of the AZ91D-alloy by up to 1.5 percent. Findings, nevertheless has exhibited that the A6 formulated composite had superior outcomes in terms of hardness. The incorporation of “reinforcing-constituent particulates” with 1.5%WGP + 7.5%Si 3 N 4 combination within the AZ91D-matrix, has further increased fatigue-strength by around 57.84 percent. A weight-loss of 0.312 mg was being unveiled for the A1 formulated fabricated composite. The weight-loss for the A6 formulated fabricated composite, however, was reported to be 0.294 mg. At 5 N loads, 2 m/s sliding speed, and 1000 m of sliding distance, the developed 1.5%WGP/7.5%Si 3 N 4 /AZ91D composites was reported to have a rate of wear, and frictional coefficient of 0.0025 mm 3 /m and 0.315, respectively. The investigation employing scanning electron microscopy (SEM) identified the presence of corrosion pits on the surfaces that had undergone corrosion. These pits were found to be a result of localised surface assaults occurring in corrosive environments. Additionally, SEM pictures of the worn surfaces indicated the emergence of microcracks, which may be associated to the conditions of cyclic loading. Moreover, the tensile-fractography examination for the developed 1.5%WGP/7.5%Si 3 N 4 /AZ91D composites has exhibited the brittle fracture failure, including cracks and debonding phenomena. In addition, the EDS spectra-analysis have revealed an apparent existence of the observed Mg-peak, Si-peak, Al-peak, Ca-peak, and O-peak for the 1.5%WGP/7.5%Si 3 N 4 /AZ91D composites. Furthermore, the utilisation of X-ray diffraction analysis effectively determined the existence of hard phases inside the AZ91D-matrix, which significantly contributed to the reported enhancement in wear resistance. The development of harder-phases has included, α-Mg, Al 12 Mg 17, SiO 2 , Si 3 N 4 , MgO, and CaO phases within the composite has been accountable for the enhancement of the tribomechanical, and wear-resistance characteristics of the AZ91D/WGP/Si 3 N 4 composites. The Si 3 N 4 has been discovered to have a substantial impact on enhancing mechanical performance and raising the resistance to wear.

• Publisher: Nature Publishing Group UK,Nature Publishing Group,Nature Portfolio
• Subject: 639/166 / 639/301 / Corrosion / Hardness / Humanities and Social Sciences / Magnesium / multidisciplinary / Particulates / Scanning electron microscopy / Science / Science (multidisciplinary) / Silicon / Silicon dioxide / Silicon nitride / Tensile strength / X-ray diffraction