Wang Yanju, Zhou Yi, Sha Aixue, Li Xingwu
Materials Evaluation Center for Aeronautical and Aeroengine Applications, AECC Beijing Institute of Aeronautical Materials, Beijing 100095, China.
Key Laboratory of Advanced Titanium Alloys, AECC Beijing Institute of Aeronautical Materials, Beijing 100095, China.
Materials (Basel). 2021 Aug 26;14(17):4841. doi: 10.3390/ma14174841.
The effect of surface integrity on the hot fatigue performance of TiAlNb alloy was investigated. A turning process was used to prepare the standard specimens for hot fatigue tests. The surface integrity characterization and axial fatigue tests were performed. The results show that the influence of surface roughness on the hot fatigue performance of the TiAlNb alloy is a secondary factor. The compressive residual stress and enhanced microhardness in the surface layer has a significant effect on the hot fatigue life and they are dominant in the hot fatigue behavior of the TiAlNb alloy. Through the investigation on the characteristics of the fatigue fractures, the fatigue propagation process was significantly suppressed because of the strong residual compressive stress and microhardness distribution on the surface layer of the TiAlNb specimen.
研究了表面完整性对TiAlNb合金热疲劳性能的影响。采用车削工艺制备热疲劳试验的标准试样。进行了表面完整性表征和轴向疲劳试验。结果表明，表面粗糙度对TiAlNb合金热疲劳性能的影响是次要因素。表层的压缩残余应力和提高的显微硬度对热疲劳寿命有显著影响，它们在TiAlNb合金的热疲劳行为中起主导作用。通过对疲劳断口特征的研究，由于TiAlNb试样表层存在较强的残余压应力和显微硬度分布，疲劳扩展过程得到了显著抑制。
