Impacts of diamond particle sizes on performance of Ni-Cu superhydrophobic coatings on drilling tool surfaces
闻棋李涛段隆臣潘秉锁
WEN Qi;LI Tao;DUAN Longchen;PAN Bingsuo
中国地质大学(武汉) 工程学院地球深部钻探与深地资源开发国际联合研究中心
在钻探工具表面施加超疏水涂层能有效缓解钻头因泥包和岩心内管堵塞所带来的挑战,然而,超疏水表面的机械稳定性不足,这一局限性在一定程度上阻碍了其在实际作业中的广泛应用。
为提高镀层的耐久性,通过复合电沉积技术将金刚石微粉共沉积于镍铜复合镀层中,并使用1H,1H,2H,2H-全氟癸基三乙氧基硅烷(1H, 1H, 2H, 2H perfluorodecyltrimethoxysilane, PFDTES)进行表面改性。采用多种测试方法研究1 μm和20 μm金刚石的质量分数对复合镀层表面形貌、粗糙度、超疏水性和超疏水耐久性的影响,结合EDS和FTIR技术分析复合镀层的化学成分,并进行了冲刷磨损实验。
结果表明:(1)高比例的1 μm金刚石促进了花椰菜状团簇的形成和发育,显著提升了镀层的超疏水性。氟化改性后镀层表面成功接枝PFDTES分子,有效降低了表面能。(2)只含有1 μm金刚石的镀层展现出最佳的微纳分级结构,具有优异的超疏水性能,接触角高达159.3°±1.5°,滚动角为0.5°±0.2°。(3)冲刷磨损实验显示,1 μm金刚石增强了花椰菜状团簇的强度和硬度,而20 μm金刚石可以保护团簇,尤其是侧面,免受石英砂的直接磨损。当1 μm金刚石质量分数为75%时,两种粒径金刚石的协同保护效果最佳,镀层展现出优异的超疏水耐久性和防泥皮结垢效果。研究成果不仅为解决钻探作业中频发的钻头泥包和钻具内壁泥皮结垢问题提供了可行的解决方案,还为增强超疏水涂层的耐久性拓展了思路,具有显著的潜在应用价值。
Applying superhydrophobic coatings on drilling tool surfaces can effectively alleviate the challenges posed by drill bit balling and core barrel blockage. However, the limited mechanical stability of superhydrophobic coatings has somewhat hindered their widespread application in practical operations.
To improve the durability of superhydrophobic coatings, this study co-deposited diamond micropowder into Ni-Cu composite coating using composite electrodeposition, followed by surface modification using 1H,1H,2H,2H-perfluorodecyltrimethoxysilane (PFDTES). Employing a variety of testing methods, this study investigated the impacts of the mass fractions of diamonds with particle sizes of 1 μm and 20 μm (also referred to as diamonds W1 and W20, respectively) on the surface morphology, roughness, superhydrophobicity, and superhydrophobic durability of the composite coatings. The chemical composition of the composite coatings was analyzed using energy-dispersive X-ray spectroscopy (EDS) and Fourier Transform Infrared (FTIR) spectroscopy, and erosion experiments on the coatings were carried out to explore their wear resistance.
The results indicate that a high proportion of diamond W1 promoted the formation and evolution of cauliflower-like clusters, significantly enhancing the coatings’ superhydrophobicity. After fluorination modification of the coatings, the PFDTES molecules were successfully grafted onto their surfaces, effectively reducing their surface energy. The coatings containing only diamond W1 exhibited the optimal micro-nano hierarchical structure. These coatings delivered excellent superhydrophobic performance, with a contact angle reaching up to 159.3° ± 1.5° and a sliding angle of 0.5° ± 0.2°. The erosion experiments revealed that diamond W1 boosted the strength and hardness of cauliflower-like clusters, while diamond W20 protected the clusters (especially their sides) from direct wear by quartz sand. When the coatings contained 75% (mass fraction) diamond W1, diamonds with two particle sizes exhibited the optimal synergistic protection effects, with the coatings demonstrating excellent superhydrophobic durability and mud cake scaling resistance. The results of this study offer a practical solution to common issues encountered during drilling, such as drill bit balling and mud cake scaling on the internal walls of drilling tools, while also introducing new ideas for enhancing the durability of superhydrophobic coatings, thus holding significant potential for application.
金刚石粒径电沉积超疏水性耐久性镍铜复合镀层钻具表面改性
diamond;particle size;electrodeposition;superhydrophobicity;durability;Ni-Cu composite coating;surface modification of drilling tools
主办单位:煤炭科学研究总院有限公司 中国煤炭学会学术期刊工作委员会