高能球磨制备NiCr-Cr_2O_3-BaF_2/CaF_2复合粉末及其爆炸喷涂层的性能  

FABRICATION OF NiCr-Cr_2O_3-BaF_2/CaF_2 COMPOSITE POWDER BY HIGH ENERGY BALL MILLING AND PROPERTIES OF IT'S DETONATION SPRAYED COATING

作　　者：张有茶[1,2] 贾成厂[1] 何利民[2] 李伟光[2] 米青田[2] 

机构地区：[1]北京科技大学材料科学与工程学院,北京100083 [2]北京航空材料研究院,北京100095

出　　处：《粉末冶金工业》2010年第2期1-6,共6页Powder Metallurgy Industry

基　　金：航空科学基金(No.KZ43070509)

摘　　要：为了制备高性能复合涂层,以70%NiCr、20%Cr2O3及10%BaF2/CaF2为原料,采用高能球磨方法制备了复合粉体,并通过特定的爆炸喷涂工艺制得复合涂层。利用扫描电子显微镜(SEM)、能谱分析(EDS)、X射线衍射(XRD)等对球磨后粉体和喷涂层的微观形貌、组织结构、成分及物相组成进行了分析。根据HB5143-96测定了爆炸喷涂复合涂层与基体间的结合强度。结果表明:随球磨时间的延长,粉体球形化程度逐步加大,颗粒尺寸逐步减小,粒度分布趋于集中,颗粒成分及结构均匀性逐步提高;当球磨11h后,粉体中的BaF2和CaF2固溶于NiCr合金,Cr2O3颗粒在NiCr基体内部镶嵌;通过爆炸喷涂将球磨粉喷涂在不锈钢基体上,其涂层微观组织均匀致密,显微硬度Hv为578,涂层与基体结合强度为67MPa,综合性能优于混合粉喷涂层。NiCr-Cr2O3-BaF2/CaF2 composite powder for detonation sprayed coating was prepared by high-energy ball milling from the mixture of 70wt%NiCr,20wt%Cr2O3 and 10wt%BaF2/CaF2 as the raw materials.The morphology,microstructure and phase composition of the powder and the sprayed coating were studied by means of scanning electron microscopy（SEM）,energy disperse spectroscopy（EDS）and X-ray diffraction（XRD）,respectively.The bond strength of coating on stainless steel matrix was measured by Instron 5882 mechine.The results indicate that,with the increase of the milling time,the degree of spheroidization of particles grows gradually,and the particle size reduces correspondingly,the particle size distribution band becomes narrower and the uniformity of composition and microstructure increases.In the composite milled for 11 hours,BaF2,CaF2 and NiCr alloy from supersaturated solid solution,and Cr2O3 disperses in NiCr matrix powder.The explosion coating made from such powder on stainlese steel is uniform and dense,with a Hv of 578,bond strength of 67 MPa,better performance than the coating made from mixed powder.

关 键 词：爆炸喷涂高能球磨固溶显微硬度结合强度 

分 类 号：TB333[一般工业技术—材料科学与工程] TG174.442[金属学及工艺—金属表面处理]