目的 旨在提高采用超音速等离子喷涂制备的Cr2O3-5%SiO2-3%TiO2涂层的耐磨等性能,探索其应用于锁渣阀工况中的可行性。方法 在Cr2O3-5%SiO2-3%TiO2复合材料中分别引入质量分数为4%的Mo和质量分数为4%的Nb2O5等2种添加剂,通过超音速等离子喷涂技术将这2种粉末沉积到316L不锈钢表面,进而制备2种新型涂层。评估涂层的微观组织和力学性能,与316L不锈钢球,通过往复摩擦实验评估其耐磨性能,并在氯化物酸性环境下进行电化学测试,评价涂层的耐腐蚀性能。结果 在Cr2O3-5%SiO2-3%TiO2涂层中加入Mo、Nb2O5后,添加Mo的涂层的断裂韧性明显提升,添加Nb2O5的涂层的硬度有所提升,其平均摩擦因数由0.576 2分别降至0.525 6、0.431 1,对磨副的整体磨损情况得到有效改善,其比磨损率由原涂层的6.4×10-5 mm3/(N·m)分别降至1.53×10-5、1.35×10-5 mm3/(N·m),涂层的耐磨性显著提高。此外,通过电化学腐蚀试验测试了涂层的耐腐蚀性,结果表明,Mo和Nb2O5的添加使得其自腐蚀电流密度从2.275×10-5 A/cm²分别降至1.103×10-6、5.937×10-7 A/cm²。EIS分析结果表明,添加Nb2O5后,其容抗弧半径最大,低频区|Z|最高。结论 Mo和Nb2O5粉末的加入有效增强了涂层的耐磨性和耐腐蚀性,改善了与316L不锈钢摩擦磨损时的性能。尤其是添加Nb2O5的涂层,其综合性能最佳,对其耐磨性提升尤为显著,涂层的磨损破坏机制主要表现为疲劳磨损与磨粒磨损共存,涂层的耐氯离子腐蚀性能得以提升,抵抗电荷转移能力增强。
Abstract
The work aims to improve the mechanical and wear properties of Cr2O3-based coatings prepared by plasma spraying through the introduction of niobium oxide (Nb2O5) and molybdenum (Mo) in an attempt to apply them to the hard sealing surfaces of slag-locking valve balls and to enhance their service life. Slag locking valves play a crucial role in coal chemical production, mainly for the precise separation of slag and slag water. However, hard seal surface wear caused by slag has become an important issue in recent years. In this study, two types of coatings were prepared by high-energy plasma jet (HEPJ) technology with a matrix consisting of Cr2O3-5%SiO2-3%TiO2. Molybdenum (4%) and niobium oxide (4%) were added to the coatings, respectively. The spraying parameters were set as follows: voltage 115 V, current 370 A, powder feeding rate 35 g/min, spraying distance 120 mm, horizontal gun travelling speed 800 mm/s, and gun perpendicular to the substrate. The resulting coating thickness was 300 μm, including a 100 μm transition layer and a 200 μm deposition layer. In order to simulate the actual working conditions, wear tests were carried out with a multifunctional wear tester (MS M9000) at a load of 15 N, with a wear length of 5 mm, a frequency of 2 Hz and a time of 60 minutes, using 316L stainless steel balls for reciprocating friction. Electrochemical corrosion tests were carried out in a mixture of 5% HCl and 5% H2SO4 with CHI600F electrochemical workstation. The experimental results showed that the addition of 4% Mo and 4% Nb2O5 decreased the porosity from (2.653±0.03)% to (1.308±0.03)% and (2.038±0.03)%, respectively, which indicated an improvement in the densification of the coatings. The mechanical properties of the coatings were all improved, and friction tests showed that the friction properties between the contact pairs were significantly improved. Specifically, the average friction coefficient decreased from 0.576 2 to 0.525 6 with the addition of Mo, and further to 0.431 1 with the addition of Nb2O5, while the depth of the wear track decreased from 13.4 μm to 4.7 μm and 3.7 μm, respectively, and the wear rate decreased from 1.58×10-5 mm3/(N·m) to 2.77×10-5 and 2.18×10-5 mm3/(N·m) respectively. It was also found that the main wear mechanisms of the coatings were fatigue wear and abrasive wear. In addition, the self-corrosion current density of the coatings decreased from 2.275×10-5 A/cm² to 1.103×10-6 A/cm² (with Mo) and 5.937×10-6 A/cm² (with Nb2O5), while the corrosion potentials increased, and the Nb2O5-added coating had the largest EIS half-arc and the highest value of |Z| in the low-frequency region, indicating that the corrosion resistance of the coating was significantly improved in the chloride ion environment. In conclusion, the addition of 4% Nb2O5 shows the best effect in improving the comprehensive performance of the coating, which not only improves the wear and corrosion resistance of the coating, but also provides a more reliable material support for slag locking valves in harsh working environments. These findings suggest that modified coatings have the potential to be an ideal solution for improving the durability and extending the service life of critical industrial components.
关键词
锁渣阀 /
超音速等离子喷涂 /
氧化铬基涂层 /
耐磨损性能 /
耐腐蚀性能
Key words
slag valve /
supersonic plasma spraying /
chromium oxide coating /
friction wear resistance /
corrosion resistance
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
参考文献
[1] 李林翰, 王春鸽, 肖柱, 等. 锡青铜阀体铸造工艺的数值模拟研究[J]. 精密成形工程, 2024, 16(12): 231-240.
LI L H, WANG C G, XIAO Z, et al.Numerical Simulation of Tin Bronze Valve Casting Process[J]. Journal of Netshape Forming Engineering, 2024, 16(12): 231-240.
[2] 曹源. 球阀的分类和设计要点浅析[J]. 化工设计, 2019, 29(4): 27-29.
CAO Y.Analysis on Classification and Design of Ball Valves[J]. Chemical Engineering Design, 2019, 29(4): 27-29.
[3] 赵刚. 煤化工锁渣阀的维修[J]. 化工管理, 2016(3): 110-111.
ZHAO G.Maintenance of Slag Lock Valve in Coal Chemical Industry[J]. Chemical Enterprise Management, 2016(3): 110-111.
[4] 杨雪华. 水煤浆工况下硬密封耐磨球阀的应用[J]. 通用机械, 2011(7): 30.
YANG X H.Application of Hard Seal Wear-Resistant Ball Valve under Coal Water Slurry Condition[J]. General Machinery, 2011(7): 30.
[5] 吴向清, 何涛, 陈连阳, 等. DN350锁渣阀磨损失效机理研究[J]. 现代制造工程, 2019(7): 131-136.
WU X Q, HE T, CHEN L Y, et al.The Wear Failure Mechanism of Lock Hopper Valve DN350[J]. Modern Manufacturing Engineering, 2019(7): 131-136.
[6] 姜南, 李聿营. Texaco煤气化装置锁渣阀的应用与改进[J]. 齐鲁石油化工, 2014, 42(4): 302-307.
JIANG N, LI Y Y.Application and Improvement of Slag Lock Valve on Texaco Coal Gasification Unit[J]. Qilu Petrochemical Technology, 2014, 42(4): 302-307.
[7] ROOS E, KOCKELMANN H, HAHN R.Gasket Characteristics for the Design of Bolted Flange Connections of Metal-to-Metal Contact Type[J]. International Journal of Pressure Vessels and Piping, 2002, 79(1): 45-52.
[8] TENMA K, KIKUCHI T, SAWA T, et al.Evaluation of Sealing Performance and FEM Calculations in Bolted Flange Connections with Ring Joint Gasket Subjected to Internal Pressure[C]// ASME 2011 Pressure Vessels and Piping Conference, 2012: 171-178.
[9] 王志强, 丘平. 煤液化装置金属硬密封耐磨球阀喷涂方法及材料的选择[J]. 石油化工设备技术, 2008, 29(4): 58-60.
WANG Z Q, QIU P.Spraying Methods and Spraying Materials Selection for Metal Sealing Ball Valve in Direct Coal Liquefaction Unit[J]. Petro-Chemical Equipment Technology, 2008, 29(4): 58-60.
[10] 蒋乐钧. 锁渣阀常用热喷涂材料耐磨耐腐蚀性能研究[D]. 银川: 宁夏大学, 2022: 37-55.
JIANG L J.Study on Wear and Corrosion Resistance of Common Thermal Spraying Materials for Slag Lock Valve[D]. Yinchuan: Ningxia University, 2022: 37-55.
[11] LI N N, LI G L, WANG H D, et al.Influence of TiO2 Content on the Mechanical and Tribological Properties of Cr2O3-Based Coating[J]. Materials & Design, 2015, 88: 906-914.
[12] ZAMANI P, VALEFI Z, JAFARZADEH K.Comprehensive Study on Corrosion Protection Properties of Al2O3, Cr2O3 and Al2O3-Cr2O3 Ceramic Coatings Deposited by Plasma Spraying on Carbon Steel[J]. Ceramics International, 2022, 48(2): 1574-1588.
[13] BASTAKYS L, MARCINAUSKAS L, MILIEŠKA M, et al. Tribological Properties of Chromia and Chromia Composite Coatings Deposited by Plasma Spraying[J]. Coatings, 2022, 12(7): 1035.
[14] 程新闯, 伏利, 陈小明, 等. 启闭机活塞杆表面高焓等离子喷涂Cr2O3·5SiO2·3TiO2/CoNiCrAlY梯度陶瓷涂层性能[J]. 粉末冶金材料科学与工程, 2021, 26(5): 436-441.
CHENG X C, FU L, CHEN X M, et al.Property of High-enthalpy Plasma Spraying Cr2O3·5SiO2·3TiO2/ CoNiCrAlY Gradient Ceramic Coating on the Surface of the Piston Rod of the Gate Hoist[J]. Materials Science and Engineering of Powder Metallurgy, 2021, 26(5): 436-441.
[15] YANG X, DONG S J, ZENG J Y, et al.Sliding Wear Characteristics of Plasma-Sprayed Cr2O3 Coatings with Incorporation of Metals and Ceramics[J]. Ceramics International, 2019, 45(16): 20243-20250.
[16] LI C L, ZHAO H X, MATSUMURA M, et al.The Effect of NiCr Intermediate Layer on Corrosion Behavior of Cr2O3 Ceramic Coated Materials[J]. Surface and Coatings Technology, 2000, 124(1): 53-60.
[17] 全国金属与非金属覆盖层标准化技术委员会. 热喷涂抗拉结合强度的测定: GB/T 8642—2002[S]. 北京: 中国标准出版社, 2002.
National Technical Committee for Standardization of Metallic and Nonmetallic Coatings. Thermal Spraying- Determination of Tensile Adhesive Strength: GB/T 8642-2002[S]. BeiJing: China Standard Press, 2002.
[18] ANSTIS G R, CHANTIKUL P, LAWN B R, et al.A Critical Evaluation of Indentation Techniques for Measuring Fracture Toughness: I, Direct Crack Measurements[J]. Journal of the American Ceramic Society, 1981, 64(9): 533-538.
[19] IOST A.Détermination de la Ténacité de Matériaux Fragiles Ou Ductiles à Partir de l'essai d'indentation[J]. Revue de Métallurgie, 110(3): 215-233.
[20] 刘正林. 摩擦学原理[M]. 北京: 高等教育出版社, 2009: 390-400.
LIU Z L.Principles of Tribology[M]. Beijing: Higher Education Press, 2009: 390-400.
[21] 孙永兴, 王引真, 何艳玲. CeO2添加剂对Cr2O3涂层组织和抗热震性的影响[J]. 稀土, 2001, 22(3): 49-52.
SUN Y X, WANG Y Z, HE Y L.Influence of Additive on the Microstructure and the Resistance to Corrosion of Plasma Sprayed Cr2O3 Coating[J]. Chinese Rare Earths, 2001, 22(3): 49-52.
[22] LEE B M, BAIK H K, SEONG B S, et al.Generation of Glass SiO2 Structures by Various Cooling Rates: A Molecular-Dynamics Study[J]. Computational Materials Science, 2006, 37(3): 203-208.
[23] ZHANG F Y, LI C, YAN S, et al.Microstructure and Tribological Properties of Plasma Sprayed TiCN-Mo Based Composite Coatings[J]. Applied Surface Science, 2019, 464: 88-98.
[24] LI C J, LUO X T, YAO S W, et al.The Bonding Formation during Thermal Spraying of Ceramic Coatings: A Review[J]. Journal of Thermal Spray Technology, 2022, 31(4): 780-817.
[25] FALS H C, LOURENÇATO L A, OROZCO M S, et al. Slurry Erosion Resistance of Thermally Sprayed Nb2O5 and Nb2O5+WC12Co Composite Coatings Deposited on AISI 1020 Carbon Steel[J]. Ceramics International, 2020, 46(17): 27670-27678.
[26] VENKATE GOWDA C, NAGARAJA T K, YOGESHA K B, et al.Study on Structural Behavior of HVOF-Sprayed NiCr/Mo Coating[J]. Journal of the Institution of Engineers (India): Series D, 2024, 105(3): 1961-1970.
[27] 刘于昌, 黄晓巍. Nb2O5对氧化铝陶瓷烧结性能和显微结构的影响[J]. 福州大学学报(自然科学版), 2006, 34(5): 708-711.
LIU Y C, HUANG X W.Effect of Nb2O5 on Sintering and Microstructure of Alumina Ceramics[J]. Journal of Fuzhou University (Natural Science Edition), 2006, 34(5): 708-711.
[28] CHEN X J, DU Y, CHUNG Y W.Commentary on Using H/E and H3/E2 as Proxies for Fracture Toughness of Hard Coatings[J]. Thin Solid Films, 2019, 688: 137265.
[29] FENG H, DAI J, LI H B, et al.Visualizing and Quantifying the Influence of N-Mo Synergy on Corrosion Resistance of Stainless Steel by Dissolution- Diffusion- Deposition Model[J]. Corrosion Science, 2024, 235: 112162.
[30] GUO P F, LIN X, LI J Q, et al.Electrochemical Behavior of Inconel 718 Fabricated by Laser Solid Forming on Different Sections[J]. Corrosion Science, 2018, 132: 79-89.
基金
浙江省温州市特种泵阀材料重点实验室专项（2024ZDSYS）
PDF(24590 KB)
渝公网安备 50010702501715号 渝ICP备15012534号-3
