Guo Yanbing, Yao Chengwu, Feng Kai, Li Zhuguo, Chu Paul K, Wu Yixiong
School of Mechanical Engineering, Shanghai Dianji University, Shanghai 201306, China.
Shanghai Key Lab of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
Materials (Basel). 2017 Jul 14;10(7):800. doi: 10.3390/ma10070800.
The growth and propagation behavior of austenite-to-bainite isothermal transformation in laser-cladded, Si-rich, and Fe-based coatings is investigated. The crystallographic features, orientation relationship at different isothermal temperatures, and the morphology of the nanostructured bainite are determined. The Nishiyama-Wassermann type orientation relationship is observed at a high temperature and at a low temperature, and mixed Nishiyama-Wassermann and Kurdjumov-Sach mechanisms are seen. The growth direction is investigated by the partial dislocation theory and an extrapolated model based on the repeated formation of lenticular-shaped subunits and pile-up along the close-packed directions of the close-packed planes. The variants of the bainite growth directions would be more selective at the high transformation temperature.
研究了激光熔覆富硅铁基涂层中奥氏体到贝氏体等温转变的生长和扩展行为。确定了纳米结构贝氏体在不同等温温度下的晶体学特征、取向关系以及形态。在高温和低温下均观察到西山- Wassermann型取向关系，并且还发现了混合的西山- Wassermann和库尔久莫夫-萨克斯机制。通过部分位错理论和基于沿密排面的密排方向重复形成透镜状亚单元和堆积的外推模型来研究生长方向。贝氏体生长方向的变体在高转变温度下将更具选择性。
