【作者】 吴玉萍； 林萍华； 王泽华； 申明霞；

【Author】 Wu Yu-ping~(1,2) Lin Ping-hua~1 Wang Ze-hua~1 Shen Ming-xia~1 1.School of Materials Science and Engineering,Hohai University,Nanjing 210098,China; 2.School of Materials Science and Engineering,Southeast University,Nanjing 210096,China

【机构】 河海大学材料科学与工程学院；

【摘要】 为了提高材料表面的硬度和耐磨性,基于超音速火焰喷涂的优点,采用超音速火焰喷涂法在1Cr18Ni9Ti不锈钢表面制备了厚度约为200μm的Fe-Cr基复合涂层。用金相显微镜、扫描电镜、X射线衍射对涂层的组织和相组成进行了研究,用显微硬度计测试了涂层的显微硬度。研究结果表明:涂层由完全熔化区(1008HV_0.2)、未熔或半熔颗粒(630HV_0.2)、白色耐蚀块状组织(650HV_0.2及孔隙组成。涂层的相为非晶、α-Fe纳米晶和几种硼化物组成。α-Fe纳米晶的尺寸约为10-50nm,纳米颗粒团聚在一起,形成100-500纳米的团簇。涂层与基体间存在5μm左右的过渡区,其成分呈梯度分布,表明两者结合良好。涂层中含有尺寸约为3-10μm和100-200nm的两种孔隙。涂层的显微硬度明显高于基体,平均硬度约(992HV_0.2)约为基体（285Hv）的3.5倍。非晶、纳米晶和硼化物的复合组织有利于提高涂层的硬度。更多还原

【Abstract】 Based on the metrits of high velocity oxy-fuel （HVOF） thermal spraying,the hardness and wear resistance of steel were improved with a Fe-Cr based coating with 200μm thickness applied to 1Cr18Ni9Ti stainless steel by HVOF thermal spraying.The microstructures and phases of the coatings were characterized using X-Ray diffraction （XRD）,optical microscopy （OM） and scanning electron microscopy （SEM）.The results show that the coating was built -up by well-flattened splat (1008HV_0.2),partially melted or unmelted particles (630HV_0.2),bright massive structure (650HV_0.2) and pores.The phases of the coating are composed of amorphous phase,a -Fe nano -size crystalline and several types of borides.The nanocrystalline grain is approximately 10-50 nm in size and the grains further formed into agglomerate-like structure with a size of 100～500nm.A graded transition region of containing elements with a width of 5μm was found,which indicated a high adhesion between the coating and the substrate.There were two types of pores with sizes of 3-10μm and 100 -200hm in the coating.The average hardness of the coating reached to 992HV and is 3. 5 times of the substrate （285HV）.The microstructures are propitious to improve the hardness of the coating.更多还原