Zhou Yutao, Yang Shufeng, Li Jingshe, Liu Wei, Dong Anping
School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China.
School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
Materials (Basel). 2018 Sep 13;11(9):1707. doi: 10.3390/ma11091707.
The characteristics and formation mechanisms of intragranular acicular ferrite (IAF) in steel with MgO nanoparticle additions were systematically investigated for different isothermal heat-treatment temperatures, and its influence on mechanical properties was also clarified. The results indicate that the inclusions were finely dispersed and refined after adding MgO nanoparticles. In addition, with decreasing heat-treatment temperature, the microstructure changed from grain boundary ferrite (GBF) and polygonal ferrite (PF) to intragranular acicular ferrite. Moreover, the steel with MgO additions had excellent mechanical properties in the temperature range of 973 to 823 K and an average Charpy absorbed energies value of around 174 J at 873 K due to the significant refinement of the microstructure and nucleation of intragranular acicular ferrite.
针对添加MgO纳米颗粒的钢，系统研究了不同等温热处理温度下晶内针状铁素体（IAF）的特征及形成机制，并阐明了其对力学性能的影响。结果表明，添加MgO纳米颗粒后，夹杂物得到了精细分散和细化。此外，随着热处理温度的降低，微观结构从晶界铁素体（GBF）和多边形铁素体（PF）转变为晶内针状铁素体。而且，添加MgO的钢在973至823 K的温度范围内具有优异的力学性能，在873 K时平均夏比吸收能量值约为174 J，这归因于微观结构的显著细化和晶内针状铁素体的形核。
