Abbasi Zeeshan Ahmad, Mateen Abdul, Niaz Akbar, Ur Rehman Muhammad Atiq, Wadood Abdul
Materials Science and Engineering Department, Institute of Space Technology, 44000 Islamabad, Pakistan.
Department of Mechanical Engineering, King Faisal University, Al Hufu̅f 31982, Saudi Arabia.
ACS Omega. 2023 Apr 18;8(17):15193-15202. doi: 10.1021/acsomega.3c00194. eCollection 2023 May 2.
Natural materials are gaining interest as coating feedstock because their "quality to cost" ratio is better and they are more environmentally friendly than most of the synthetic ceramics. They give sufficient protection to metal surfaces against harsh conditions such as corrosion, wear, and high temperature. In the current study, chromite mineral was beneficiated and reduced to two different sizes to be used as feedstock material for thermal spray coating. Powders were upgraded by gravity and magnetic separation, respectively, and thermally sprayed onto mild steel samples by using atmospheric plasma spray (APS) equipment. Morphology, structure, phases, elemental distribution of chromite powder, and coatings were studied using field emission scanning electron microscopy, X-ray diffraction, X-ray fluorescence spectroscopy, and energy-dispersive X-ray spectroscopy. Tribological properties of APS chromite coatings were investigated by using a ball-on-disk tribometer, and corrosion resistance properties were evaluated by carrying out potentiodynamic polarization testing in 3.5% NaCl solution. It is observed that the coating has better wear and corrosion resistance and is worn by abrasive wear that includes scratching and particles pull out. Coating efficiency, surface morphology, and microhardness of the coating developed by fine powder were better than those of coarse powder coating.
天然材料作为涂层原料正受到越来越多的关注，因为它们的“质量成本”比更高，而且比大多数合成陶瓷更环保。它们能为金属表面提供足够的保护，使其免受腐蚀、磨损和高温等恶劣条件的影响。在当前的研究中，对铬铁矿进行了选矿，并将其粉碎成两种不同的尺寸，用作热喷涂涂层的原料。粉末分别通过重力分离和磁选进行提纯，并使用大气等离子喷涂（APS）设备热喷涂到低碳钢样品上。利用场发射扫描电子显微镜、X射线衍射、X射线荧光光谱和能量色散X射线光谱研究了铬铁矿粉末和涂层的形貌、结构、相、元素分布。利用球盘摩擦磨损试验机研究了APS铬铁矿涂层的摩擦学性能，并通过在3.5%NaCl溶液中进行动电位极化测试来评估其耐腐蚀性。观察到涂层具有更好的耐磨性和耐腐蚀性，磨损方式为磨粒磨损，包括划痕和颗粒脱落。细粉制备的涂层的涂层效率、表面形貌和显微硬度均优于粗粉涂层。
