Chintada Vinod Babu, Uppada Sudhakar, Gurugubelli Thirumala Rao, Koutavarapu Ravindranadh, Alharthi Salman S
Department of Mechanical Engineering, GMR Institute of Technology, GMR Nagar, Rajam, Andhra Pradesh 532127, India.
Department of Physics, School of Sciences & Humanities, SR University, Warangal, Telangana 506371, India.
iScience. 2025 May 15;28(6):112680. doi: 10.1016/j.isci.2025.112680. eCollection 2025 Jun 20.
Electroless Ni-P coatings are ideal for automotive steel components, such as brake pads, as they offer exceptional adhesion, corrosion resistance, and hardness. In this study, duplex coatings were developed by combining zinc oxide (ZnO), aluminum oxide (AlO), and silicon carbide (SiC) nanoparticles in four different forms: Ni-P-ZnO/SiC, Ni-P-SiC/ZnO, Ni-P-AlO/SiC, and Ni-P-SiC/AlO. These coatings were subjected to an annealing process at 200°C for 120 min in order to assess the impact of heat treatment. XRD, SEM, Vickers hardness experiments, and potentiodynamic polarization in a 3.5% NaCl solution were employed to evaluate the corrosion behavior, microhardness, and surface roughness. Although Ni-P-SiC/AlO coatings exhibited the highest microhardness (37% increase), the results indicated that Ni-P-AlO/SiC coatings had the lowest surface irregularity (0.74 μm). Ni-P-ZnO/SiC coatings demonstrated superior corrosion resistance with a corrosion potential of -490 mV. The coatings exhibited an increase in crystallinity following annealing, which subsequently enhanced their corrosion resistance and hardness.
化学镀镍磷涂层对于汽车钢部件（如刹车片）来说是理想的，因为它们具有出色的附着力、耐腐蚀性和硬度。在本研究中，通过将氧化锌（ZnO）、氧化铝（AlO）和碳化硅（SiC）纳米颗粒以四种不同形式组合来制备复合涂层：Ni-P-ZnO/SiC、Ni-P-SiC/ZnO、Ni-P-AlO/SiC和Ni-P-SiC/AlO。为了评估热处理的影响，这些涂层在200°C下进行120分钟的退火处理。采用X射线衍射（XRD）、扫描电子显微镜（SEM）、维氏硬度实验以及在3.5%氯化钠溶液中的动电位极化来评估腐蚀行为、显微硬度和表面粗糙度。尽管Ni-P-SiC/AlO涂层表现出最高的显微硬度（增加了37%），但结果表明Ni-P-AlO/SiC涂层具有最低的表面不规则度（0.74μm）。Ni-P-ZnO/SiC涂层表现出优异的耐腐蚀性，其腐蚀电位为-490mV。退火后涂层的结晶度增加，随后提高了它们的耐腐蚀性和硬度。
