| 摘要: |
| 超音速火焰喷涂（HVOF）制备的WC基金属陶瓷涂层广泛应用于金属构件的磨损、腐蚀及空蚀防护。分别采用氢气燃料及煤油液体燃料HVOF喷涂设备分别在9种不同的工艺条件下制备了WC10Co4Cr涂层，研究了燃料类型对涂层的组织、残余应力及力学性能的影响规律。在两种燃料HVOF工艺各自优化的喷涂参数条件下，通过对基体曲率的原位监测对比测试了涂层中的平均残余应力；利用显微维氏硬度、压痕法（断裂韧性）和球盘摩擦磨损对比研究了涂层的力学性能。结果表明：液体燃料（LF）HVOF焰流中粒子的温度更低，速度更高。LF-HVOF喷涂的WC10Co4Cr涂层内的残余压应力更高且涂层致密度更高，而气体燃料（GF）HVOF喷涂的WC10Co4Cr涂层内为残余拉应力。LF-HVOF涂层（1280 HV0.3， 7.3 MPa·m0.5）比GF-HVOF涂层（1032 HV0.3， 4.5 MPa·m0.5）具有更高的硬度和断裂韧性，LF-HVOF涂层的耐磨性约为GF-HVOF涂层的1.7倍。 |
| 关键词: 超音速火焰喷涂 燃料类型 WC10Co4Cr涂层 残余应力 力学性能 |
| DOI：10.11933/j.issn.1007-9289.20190405001 |
| 分类号:TG174.442 |
| 基金项目:中国华能集团科技项目（HNKJ17-H22-02） |
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| Effects of Fuel Type and Spraying Parameters on Microstructure and Mechanical Properties of HVOF Sprayed WC10Co4Cr Coatings |
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YANG Erjuan, LI Yong, LI Wei, LI Taijiang, WANG Bo, MI Zihao, LIU Gang
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Xi'an Thermal Power Research Institute Co., Ltd., Xi'an 710054, China
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| Abstract: |
| HVOF sprayed WC-based cermet coatings have been widely used in industries for wear, corrosion and cavitation protection of the metallic components. WC10Co4Cr coatings were deposited by gas fuel-HVOF (GF-HVOF) and liquid fuel-HVOF (LF-HVOF) processes at 9 different spraying conditions to investigate the effect of fuel type on microstructure, residual stress and mechanical properties of HVOF cermet coatings. For the coatings prepared at optimized conditions, residual stress raised in the coatings was in-situ monitored by testing the curvature evolution of the substrate during spraying. Vickers microhardness, indentation and ball-on-disc wear test were performed to evaluate mechanical properties of the resultant cermet coatings. The results show that cermet particles have higher velocity and lower surface temperature in LF-HVOF than those in GF-HVOF. A compressive residual stress is formed in the LF-HVOF WC10Co4Cr coating while a residual stress is detected in the GF-HVOF coating. Because of combination of more compact microstructure and compressive residual stress, the LF-HVOF cermet coating (1280 HV0.3, 7.3 MPa·m0.5) shows both higher hardness and higher fracture toughness and thereby higher wear resistance than that of CF-HVOF coating (1032 HV0.3, 4.5 MPa·m0.5). |
| Key words: high velocity fuel spray fuel type WC10Co4Cr coating residual stress mechanical properties |
