HVOF热喷涂制备Fe基非晶合金涂层的微观结构和摩擦磨损性能研究  

Microstructure and wear behavior of Fe-based amorphous metallic coating by HVOF thermal spraying

作　　者：H.H.Yao Z.Zhou K.Z.Tang Z.Tan G.H.Wang D.Y.He 王玉 

机构地区：[1]北京理工大学材料科学与工程学院

出　　处：《热喷涂技术》2017年第4期50-57,共8页Thermal Spray Technology

摘　　要：通过高速氧燃料火焰喷涂制备一种Fe59Cr12Nb5B20Si4非晶金属涂层,与商用316L不锈钢相比,以实现更低的热导率和更好的耐磨防护效果。所制备的涂层具有致密层状结构(孔隙率小于1%),有轻微的氧化发生。Fe基涂层的微观结构中具有非晶骨架并有纳米晶析出,其热导率(2.66 W/m K)显著低于不锈钢涂层(5.87 W/m K)。得益于这种微观结构,涂层硬度可达到1258±92 HV。因为涂层磨损机理的改变,涂层的摩擦系数和磨损量在200℃时上升,并在400℃时下降。涂层在室温时的磨损机理主要为疲劳磨损并伴有氧化磨损。在200℃时,由于第三粒的磨损,磨损过程加速。400℃下涂层耐磨性能的下降可能导致大面积的氧化膜的生成。To manufacture a protective coating with low thermal conductivity and good frictional wear performance, a Fe59Cr12Nb5B20Si4 was designed and produced to prepare coating by High velocity oxygen fuel （HVOF） spraying, in comparison with commercially stain steel AISI 316L coating. Both as deposited coatings exhibit dense layered structure with porosity below 1% and slight oxidation. The microstructure of Fe-based coating composes of amorphous matrix and some precipitated nanocrystals, resulting in the thermal conductivity of designed Fe-based coating （2.66 W/mK） is significantly lower than that of stain steel coating 316L （5.87 W/mK）. Depending on the structure advantage, the Fe-based coating exhibits higher microhardness, reaching to 1258 ± 92 HV. The friction coefficient and wear rate of Fe-based coating display an increase at 200 ℃ followed by a decrease at 400 ℃ determined by the evolution of wear mechanism at different temperature. The dominant wear mechanism of Fe-based coating at room temperature is fatigue wear accompanying with oxidative wear. At 200 ℃ , due to the existence of “third body” abrasive wear, the wear process was accelerated. The large-area oxide layer is supposedly responsible for the decrease of friction of the coating at 400 ℃ .

关 键 词：摩擦磨损性能 合金涂层 微观结构 非晶 制备 HVOF Fe 热喷涂 

分 类 号：TG174.442[金属学及工艺—金属表面处理]