摘要
采用激光熔覆技术在Q235钢表面制备了CoCrFeNiMox(x=0.1、0.2、0.3)高熵合金涂层,考察了钼含量对涂层性能的影响。通过扫描电镜、X射线衍射仪、能谱仪和硬度仪表征了涂层的相结构、微观形貌、组织结构、元素成分和显微硬度,并进行了摩擦磨损试验,研究了涂层的磨损机制。结果表明,CoCrFeNiMo0.1、CoCrFeNiMo0.2高熵合金涂层由fcc相组成,CoCrFeNiMo0.3高熵合金涂层则由fcc相和σ相组成。涂层的组织主要为树枝晶,并存在Mo、Cr等元素的偏聚,在结合区附近容易产生裂缝等缺陷。随着Mo元素增多,偏析现象得到缓解,缺陷明显减少,且由于高熵合金晶格畸变效应、σ相析出等因素的共同作用,涂层的硬度随之不断提升,摩擦因数、磨损质量损失和磨损率不断减小。CoCrFeNiMo0.3涂层的磨损质量损失仅为CoCrFeNiMo0.1涂层的45%。通过三维形貌测量仪观察磨痕可以发现,涂层的磨损机制主要为磨粒磨损,CoCrFeNiMo0.1涂层还伴随有黏着磨损。
CoCrFeNiMox(x=0.1,0.2,0.3)high-entropy alloy coatings were prepared on the surface of Q235 steel by laser cladding,and the effect of molybdenum content on properties of the coatings were studied.The phase constitution,micro-morphology,microstructure,elemental composition,and microhardness of the coatings were characterized using scanning electron microscope,X-ray diffractometer,energy-dispersive spectrometer,and hardness tester,and the wear mechanism was analyzed through friction and wear testing.The results showed that the CoCrFeNiMo0.1 and CoCrFeNiMo0.2 high-entropy alloy coatings are composed of fcc phase,while the CoCrFeNiMo0.3 high-entropy alloy coating is composed of fcc andσphases.The coatings have a typical dendritic structure,along with a segregation of molybdenum,chromium,and other elements,which likely leads to the formation of defects such as cracks near the bonding areas.With the increasing of molybdenum content,the segregation is relieved,the defects are significantly reduced,the hardness of the coatings is increased and the friction factor,mass loss,and wear rate are decreased due to the effect of lattice distortion and the generation of hard phases.The mass of loss for the CoCrFeNiMo0.3 alloy coating after wearing test was only 45%that of the CoCrFeNiMo0.1 alloy coating.The wear scars were observed via a three-dimensional profilometer and it was found that the wear mechanism of the coatings is mainly abrasive wear,which is accompanied by adhesive wear for the CoCrFeNiMo0.1 coating.
作者
王昕阳
黄燕滨
刘谦
谢璐
许诠
黄俊雄
WANG Xinyang;HUANG Yanbin;LIU Qian;XIE Lu;XU Quan;HUANG Junxiong(Army Academy of Armored Forces,Beijing 10072,China;不详)
出处
《电镀与涂饰》
CAS
CSCD
北大核心
2020年第17期1201-1208,共8页
Electroplating & Finishing
关键词
高熵合金
钴铬铁镍钼
激光熔覆涂层
碳钢
耐磨性
组织结构
high-entropy alloy
cobalt-chromium-iron-nickel-molybdenum
laser-clad coating
carbon steel
wear resistance
microstructure
