Titanium dioxide (TiO₂) has been a key material in a wide range of applications such as catalysis, energy harvesting, and antibacterial surfaces. Typically, different TiO₂ phases are first synthesized and then coated onto the test parts. Here, the authors demonstrate a direct method for the formation of TiO₂ nanostructures and patterns with rutile, anatase, and mixed phases by a controlled laser-assisted surface modification approach on additive manufacturing titanium parts. A tunable nanosecond fiber laser coupled to a galvo scanner was employed to regulate the laser material for a controlled and localized transformation process in an oxygen environment. The influence of processing conditions such as scanning speed, laser power, laser pulse duration, frequency, and gas flow rate on the selective formation of rutile, anatase, and mixed phases was studied. The structural evolutions and morphology have been investigated using different characterization techniques, including scanning electron microscopy and Raman spectroscopy methods. The main advantage of this laser-assisted process is its ability to create selective TiO₂ phases on complex titanium parts such as implants.

中文翻译：

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钛的激光辅助选择性和局部表面转化为锐钛矿，金红石和混合相纳米结构

二氧化钛（TiO ₂）已成为广泛应用的关键材料，例如催化，能量收集和抗菌表面。通常，首先合成不同的TiO ₂相，然后将其涂覆到测试部件上。在这里，作者演示了直接形成TiO _2的方法通过可控的激光辅助表面改性方法在增材制造钛零件上形成具有金红石，锐钛矿和混合相的纳米结构和图案。耦合到振镜扫描器的可调纳秒光纤激光器用于调节氧气材料，以便在氧气环境中进行受控和局部的转换过程。研究了诸如扫描速度，激光功率，激光脉冲持续时间，频率和气体流速等处理条件对金红石，锐钛矿和混合相选择性形成的影响。使用不同的表征技术，包括扫描电子显微镜和拉曼光谱法，研究了结构演变和形态。这种激光辅助工艺的主要优点是能够产生选择性的TiO ₂ 复杂的钛零件（例如植入物）上的相。