离子注入AZ91镁合金表面结构和耐蚀性能研究

Study on Surface Structure and Corrosion Resistance of AZ91 Alloy After Injecting Ion

为改善AZ91镁合金的耐蚀性能,对AZ91镁合金表面进行不同种类离子注入(N、Cr、N+Cr)。通过X射线衍射仪(XRD)、扫描电镜(SEM)、电化学腐蚀系统和显微硬度仪分析了离子注入前后表面结构、耐蚀性能和显微硬度的变化。结果表明:基体由Mg和Al12Mg17相组成,注入后的试样形成了注入元素与基体元素间的金属间化合物和以固溶形式存在的注入元素。扫描电镜清晰地观察到双离子注入后试样的晶界和不同的相组织结构,说明离子注入对基体产生了明显的溅射作用。注入后自腐蚀电位和显微硬度都得到一定程度的提高,N离子注入试样的显微硬度提高达38.8%。

In order to improve the corrosion resistance of AZ91 alloy, different ions （N, Cr, N＋Cr） was implanted into the surface of magnesium alloy. The surface structure, corrosion resistance and microhardness of different treated samples were analyzed using XRD, SEM, electrochemical testing system and micro-hardness tester. The results show that the surface modified layer includes Mg, Al12Mg17, implanted elements and compounds. SEM founds grain boundary and phase microstrueture of duplex implant sample, ions sputtering process is obvious. The flee corrosion voltage and microhardness of the alloy after implanting enhance, the microhardness of N ion implanted sample increases by 38.8%.