等离子喷涂钼基非晶纳米晶复合涂层的组织和电化学特性

Microstructure and electrochemical properties of molybdenum base amorphous and nanocrystalline alloy coatings by plasma spraying

摘要: 用Mo基合金粉末(含Si,B,Cr,W,Mo,Ni等)作为喷涂材料,利用大气等离子喷涂(APS)技术,在0Cr13Ni5Mo不锈钢基体上制备了钼基非晶纳米晶复合涂层.利用XRD观察了涂层的晶型结构,扫描电镜(SEM)观察涂层的组织形貌,恒电位扫描仪对涂层的电化学特性进行了测试,显微硬度仪测量涂层的显微硬度.实验结果表明,利用等离子喷涂工艺可以制备高硬度的Mo基非晶纳米晶复合涂层,这种涂层结构均匀致密,其显微硬度最高达到1426.9HV.孔隙率约为5.5%.非晶纳米晶复合涂层在3.5%NaCl溶液中存在钝化现象,自腐蚀电流为6.459μA·cm^-2,腐蚀速度0.869mm·a^-1.

Abstract: A coating was prepared on 0Cr13Ni5Mo stainless steel by air plasma spraying with a kind of molybdenum base alloy powder which contains Si, B, Cr, W, Mo, Ni etc. as the plasma spraying powder. It was proved that the Mo-base alloy coating fabricated by air plasma spraying has homogenous microstructure and contains metal glass and nanocrystals by X-ray diffractometer, SEM, TEM and Potentionstat/Galvanostat Model 273. The coating has high hardness and the highest micro-hardness can reach 1 426.9 HV. The porosity is about to 3.1%. Experimental results also show that Mo-base amorphous and nanocrystalline alloy coatings can appear a passivation phenomenon in a 3.5% NaCl solution with I_corr(R)=6.459μA·cm^-2 and E (I=0)=0.869 mm·a^-1.