Biomaterial and Material for Dental Treatment, Faculty of Dentistry, Chulalongkorn University, Bangkok, 10330, Thailand.
Metallurgy and Materials Science Research Institute (MMRI), Chulalongkorn University, Bangkok, 10330, Thailand.
J Nanosci Nanotechnol. 2019 Jul 1;19(7):3804-3810. doi: 10.1166/jnn.2019.16327.
The aim of this study was to evaluate the mechanical and tribological properties of graphene oxide/silver nanoparticle (GO/AgNP) coated medical grade nickel-titanium (NiTi) alloy. The alloy substrates were coated using electrophoretic deposition at 30 V for 1, 5, and 10 min and were characterized by SEM, Raman spectroscopy, EDS, and surface profilometer. Mechanical and tribological tests were performed for hardness, Young's modulus, and friction coefficient. The data were analyzed using the Kruskal-Wallis test at a significance level of 0.05 to compare the coatings' roughness, thickness, friction coefficient, and hardness at the different coating times. The GO/AgNP coatings were confirmed with Raman spectroscopy, which demonstrated the presence of D bands and G bands at ∼1300 cm and ∼1600 cm. The intensity ratios of the D and G bands (/) were 0.838, 0.836, and 0.837 in the 1, 5, and 10 min coated groups, respectively. The coating thickness ranged from 0.46-1.34 m and the mean surface roughness (Ra) ranged from 50.72-69.93 nm. Increasing the coating time from 1-10 min increased the roughness, thickness, and Young's modulus of surface coating. The friction coefficients of the coated NiTi alloy were significantly lower compared with that of the uncoated NiTi allloy ( < 0.001). The GO/AgNP nanocomposite coated NiTi alloy demonstrated improved mechanical strength and a reduced friction coefficient that would be more favorable for biomedical applications.
本研究旨在评估氧化石墨烯/银纳米粒子（GO/AgNP）涂层的医用级镍钛（NiTi）合金的机械和摩擦学性能。合金基底采用 30 V 的电泳沉积法在 1、5 和 10 分钟内进行涂层，并通过 SEM、拉曼光谱、EDS 和表面轮廓仪进行表征。进行了硬度、杨氏模量和摩擦系数的机械和摩擦学测试。使用 Kruskal-Wallis 检验对数据进行分析，显著性水平为 0.05，以比较不同涂层时间下涂层的粗糙度、厚度、摩擦系数和硬度。GO/AgNP 涂层通过拉曼光谱得到证实，在约 1300 cm 和约 1600 cm 处显示出 D 带和 G 带的存在。在 1、5 和 10 分钟涂层组中，D 带和 G 带的强度比（/）分别为 0.838、0.836 和 0.837。涂层厚度范围为 0.46-1.34 μm，平均表面粗糙度（Ra）范围为 50.72-69.93 nm。从 1 分钟到 10 分钟的涂层时间增加，增加了表面涂层的粗糙度、厚度和杨氏模量。与未涂层的 NiTi 合金相比，涂层的 NiTi 合金的摩擦系数显著降低（<0.001）。GO/AgNP 纳米复合材料涂层的 NiTi 合金表现出改善的机械强度和降低的摩擦系数，这将更有利于生物医学应用。
