为了改善血管支架材料316L不锈钢的耐腐蚀性和血液相容性，分别采用混合酸(2%HF+10%HNO3,体积分数)钝化和高温热处理钝化方法对机械抛光的316L不锈钢进行原位表面改性，通过X射线衍射仪(XRD)、原子力显微镜(AFM)和带能谱仪的扫描电子显微镜(SEM-EDS)分析改性前后316L不锈钢的表面成分和形貌，通过电化学性能测试和接触角测试来分析改性前后316L不锈钢的耐腐蚀性和润湿性.结果表明：混合酸钝化的316L不锈钢表面主要是Cr-O氧化膜，高温热处理钝化的316L不锈钢表面为Fe2O3与Cr-O混合物氧化膜，均起到了改善316L不锈钢在模拟人体体液环境中的耐腐蚀性的作用；2种方法改性后的316L不锈钢表面均呈亲水性，且使得316L不锈钢表面能的极化分量增加，材料与血液间界面张力减小，均可作为生物医用材料使用，并能够改善316L不锈钢的耐腐蚀性和血液相容性.
In order to improve the corrosion resistance and hemocompatibility of 316L stainless steel, mechanical polished 316L stainless steel was modified in situ by mixed acid (2%HF+10%HNO3, volume fraction) immersion and high-temperature treatment. The surface morphologies of 316L stainless steel and modified 316L stainless steel were characterized by X-ray diffraction (XRD), atom force microscopy (AFM) and scanning electron microscope with energy dispersion spectrometer (SEM-EDS). The corrosion resistance and wettability of 316L stainless steel and modified 316L stainless steel were analyzed by electrochemical and contact angle measurement respectively. The results indicated that Cr-O oxidation films were formed on 316L stainless steel after mixed acid immersion. Fe2O3 and Cr-O mixed oxidation films were grown on the high-temperature treatment 316L stainless steel. The corrosion resistance of modified 316L stainless steel was improved in simulated body fluid. The surface of 316L stainless steel modified by the two methods was hydrophilic. The surface energy polarization component of mixed acid immersion and high-temperature treatment 316L stainless steel were all increased. While, the interfacial tension between the materials and blood was decreased. Mixed acid passivation and high-temperature treated can improve the corrosion resistance and hemocompatibility properties of 316L stainless steel.
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