导电辊用铁基非晶及纳米晶涂层在NaOH,H2SO4和NaCl溶液中的腐蚀行为研究

Corrosion behavior of Fe-based amorphous and nanocrystalline coatings on conductive roller in NaOH, H2SO4 and NaCl solution

采用FeCrMnMoWBCSi的母合金,通过铜模吸铸法,气雾化方法制备非晶合金粉末,然后用超音速火焰喷涂制作涂层;分别采用不同温度320℃、480℃与650℃在箱式电阻炉内对3组试样进行退火处理制备纳米晶涂层,非晶和纳米晶双物相涂层;SEM电镜观察非晶合金粉末尺寸及形状;经X射线衍射和电化学测试非晶及纳米晶涂层等手段,考察了铁基非晶及纳米晶涂层在NaOH,H2SO4和NaCl溶液中的电化学腐蚀行为.结果表明:导电辊采用铁基HVOF喷涂作为外保护层时,在NaOH碱液采用经非晶退火后的纳米晶为佳,在H2SO4和NaCl溶液中使用时,外保护层可为纳米晶,或为非晶和纳米晶双物相状态皆可.

FeCrMnMoWBCSi master alloy was used to prepare amorphous alloy powder by copper mould suction casting and aerosol spraying methods.Then,the coating was made by supersonic flame spraying.Nanocrystalline coatings,amorphous coatings and nanocrystalline biphase coatings were prepared by annealing three groups of samples in a box-type resistance furnace at different temperatures 320℃,480℃and 650℃respectively.The amorphous alloy powder was observed by means of SEM electron microscope,and coatings were measured by X-ray diffraction and electrochemical test.The results of electrochemical corrosion behavior in NaOH,H2SO4 and NaCl solutions showed that when the conductive roller is coated with Fe-based HVOF,it is better to use nanocrystals after amorphous annealing in NaOH lye.When it is used in H2SO4 and NaCl solutions,the coating can be nanocrystals,or both amorphous and nanocrystals.