AlNiZr非晶纳米晶复合涂层的腐蚀磨损行为研究

Study on Tribocorrosion Behaviors of AlNiZr Amorphous and Nanocrystalline Composite Coatings

为提高海洋极端环境下钢结构材料的耐腐蚀磨损性能,采用高速电弧喷涂技术制备了一种AlNiZr非晶纳米晶复合涂层,并研究了该涂层在质量分数为3.5%的NaCl溶液中的腐蚀磨损行为。结果发现,AlNiZr涂层组织较为均匀,致密性较好,相结构由非晶、纳米晶及晶化相共同组成,涂层非晶体积分数约为64.93%,平均显微硬度值为363HV0.1,与45钢基体之间的平均结合强度约为30.8 MPa;在干摩擦条件下其平均摩擦因数约为0.125,磨损体积约为0.134 mm^(3),磨痕宽度约为882.4μm,磨损失效机制以氧化磨损和脆性剥层磨损为主,并伴有轻微磨粒磨损;在腐蚀介质条件下,由于受到腐蚀介质的润滑减摩作用,导致涂层的平均摩擦因数、磨损体积、磨痕宽度均有明显减小,其平均摩擦因数约为0.058,磨损体积约为0.02216 mm^(3),磨痕宽度约为314μm,腐蚀磨损失效机制主要表现为剥层磨损形式,同时磨损起主导作用、腐蚀次之。与纯铝涂层相比,AlNiZr涂层表现出优异的耐腐蚀磨损性能。

In order to improve the corrosion and wear resistance of steel structure materials in marine extreme environments,a new kind of AlNiZr amorphous and nanocrystalline composite coating was prepared by high velocity arc spraying technology.The tribocorrosion behaviors of the AlNiZr coatings in 3.5 wt.%NaCl solution were studied.The results show that the arc-sprayed AlNiZr coatings have uniform microstructure and good density.The phase structure is composed of amorphous,nanocrystalline and crystalline phases.The volume fraction of amorphous phases in AlNiZr coatings is as about 64.93%,the average microhardness value is as 363 HV0.1,and the average bonding strength between the coatings and 45 steel is as about 30.8 MPa.Under the dry friction conditions,the arerage friction factor,wear volume and wear width of AlNiZr coatings are about 0.125,0.134 mm^(3),and 882.4μm,respectively.The wear failure mechanism of the coatings is mainly oxidative wear and brittle delamination wear,accompanied by slight abrasive wear.Under the corrosive conditions,the average friction factor,wear volume and wear width of the coatings decrease significantly due to the lubrication and antifriction of corrosive medium,which are about 0.058,0.02216 mm^(3) and 314μm,respectively.The corrosion wear failure mechanism of the coatings mainly exhibites in the form of delamination wear,and wear plays a leading role,followed by corrosion.Compared with the pure aluminum coatings,the AlNiZr coatings show excellent corrosion and wear resistance.