喷焊余温淬火改善深松铲尖铁基涂层耐磨性  

Improvement of wear resistance of deep-shovel tip with Fe-based alloy coating by flame spray welding residual temperature quenching

作　　者：赵建国[1] 李建昌[1] 王安[1] 马璐萍[1] 郝建军[1] 张晋国[1] 马跃进[1] 

机构地区：[1]河北农业大学机电工程学院,保定071001

出　　处：《农业工程学报》2018年第3期65-71,共7页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家"十三五"科技支撑重大项目粮食丰产增效科技创新专项课题(2017YFD0300907);河北农业大学理工基金重点项目(ZD201616)

摘　　要：针对深松铲尖耐磨性能差、失效频繁等问题,采用火焰喷焊技术在45钢基体上制备了铁基合金涂层,并利用喷焊后试件余温对其进行了淬火处理。利用扫描电镜、能谱仪、X射线仪分析了涂层显微组织、元素构成及物相组成,利用显微硬度计、磨损试验机测试了涂层显微硬度及磨损性能。结果表明,涂层与基体呈良好冶金结合,淬火涂层主要由碳化物Cr_(23)C_6、Cr_7C_3,硼化物Fe_2B,复合相(Cr,Fe)_7C_3以及固溶体γ-Fe(Cr,Ni,C,Si)等组成。与未淬火涂层相比,组织得到细化,涂层显微硬度平均为800 HV左右,较未淬火涂层提高了约100 HV。淬火涂层试件(45钢基体)和未淬火涂层试件(45钢基体)平均磨损质量分别为0.30和0.35 g;田间试验的涂层淬火深松铲尖(65Mn基体)磨损质量为32 g,无涂层65Mn铲尖为70 g,涂层深松铲尖具有较好的耐磨性,该研究可为延长深松铲尖使用寿命提供参考。There is a problem that subsoiling shovel tips are poor in wear resistance and lose effectiveness frequently.In order to solve the problems of poor wear resistance and frequent failure,Fe-Cr-Ni alloy coating was prepared on 45 steel substrate using flame spray welding process.And the spray welding coating has been quenched using the specimen residual temperature.The quenching temperature is 800℃.Microstructure,composition and phase of alloy coating were analyzed by scanning electron microscope,energy dispersive spectrometer,and X-ray diffraction.The microhardness was tested by microhardness tester.The wear properties were tested by soil abrasive wear testing machine.The results showed that the coating zone,binding zone and substrate zone are obvious,metal interpenetration phenomenon has been found in binding zone,and metallurgical bonding can be achieved between the coating and substrate.The good metallurgical bonding can be obtained between the coating and iron substrate.The alloy coating consists of carbide Cr_7C_3 and Cr_（23）C_6,boride Fe_2B,（Cr,Fe）_7C_3 and solid solutionγ-Fe（Cr,Ni,C,Si）and（Fe,Ni）.On the effect of oxygen and acetylene hot resource,Fe and Cr elements in the alloy were heated to molten state,and then Fe,Cr and C,B were combined to form carbide and boride.As the role of the austenite stable element Ni,there isγ-Fe（Cr,Ni,C,Si）solid solution formed in the coating,which is helpful to reduce the brittleness of the spray welding layer.Compared with the unquenched coating,the microstructure of quenched coating is refined,and the hard phase is shown as rectangular block,lozenge block and ball block,whose size is from 5 to 20μm.The microhardness of the quenched coating can reach up to 900 HV,and the average microhardness is about 800 HV,increased by about 100 HV compared with the unquenched coating.The contrast tests have been carried out between quenched coating,unquenched coating and 65 Mn subsoiling shovel tip.The average wear loss of quenched coating is about 0.30 g,that of

关 键 词：农业机械 涂层 显微组织 深松铲尖 火焰喷焊 铁铬镍合金涂层 耐磨性 

分 类 号：TG174.4[金属学及工艺—金属表面处理]