Milosan Ioan, Florescu Monica, Cristea Daniel, Voiculescu Ionelia, Pop Mihai Alin, Cañadas Inmaculada, Rodriguez José, Bogatu Cristina Aurica, Bedo Tibor
Faculty of Materials Science and Engineering, Transilvania University of Brasov, 1 Universitatii Street, 500068 Brasov, Romania.
Faculty of Medicine, Transilvania University of Brasov, 1 Universitatii Street, 500068 Brasov, Romania.
Materials (Basel). 2020 Jan 26;13(3):581. doi: 10.3390/ma13030581.
The appropriate selection of implant materials is very important for the long-term success of the implants. A modified composition of AISI 316 stainless steel was treated using solar energy in a vertical axis solar furnace and it was subjected to a hyper-hardening treatment at a 1050 °C austenitizing temperature with a rapid cooling in cold water followed by three variants of tempering (150, 250, and 350 °C). After the heat treatment, the samples were analyzed in terms of hardness, microstructure (performed by scanning electron microscopy), and corrosion resistance. The electrochemical measurements were performed by potentiodynamic and electrochemical impedance spectroscopy in liquids that simulate biological fluids (NaCl 0.9% and Ringer's solution). Different corrosion behaviors according to the heat treatment type have been observed and a passivation layer has formed on some of the heat-treated samples. The samples, heat-treated by immersion quenching, exhibit a significantly improved pitting corrosion resistance. The subsequent heat treatments, like tempering at 350 °C after quenching, also promote low corrosion rates. The heat treatments performed using solar energy applied on stainless steel can lead to good corrosion behavior and can be recommended as unconventional thermal processing of biocompatible materials.
对于植入物的长期成功而言，植入材料的恰当选择非常重要。一种改良成分的AISI 316不锈钢在垂直轴太阳能炉中利用太阳能进行处理，并在1050°C的奥氏体化温度下进行超硬化处理，随后在冷水中快速冷却，接着进行三种回火处理（150、250和350°C）。热处理后，对样品进行了硬度、微观结构（通过扫描电子显微镜进行）和耐腐蚀性分析。通过动电位和电化学阻抗谱在模拟生物流体的液体（0.9%氯化钠溶液和林格氏溶液）中进行电化学测量。观察到根据热处理类型不同的腐蚀行为，并且在一些热处理样品上形成了钝化层。通过浸入淬火进行热处理的样品表现出显著提高的点蚀抗性。随后的热处理，如淬火后在350°C回火，也能促进低腐蚀速率。对不锈钢应用太阳能进行的热处理可导致良好的腐蚀行为，并且可作为生物相容性材料的非常规热加工方法予以推荐。
