Małecka Joanna, Rozumek Dariusz
Faculty of Mechanical Engineering, Opole University of Technology, 45-271 Opole, Poland.
Materials (Basel). 2020 Jul 6;13(13):3006. doi: 10.3390/ma13133006.
This paper provides the test results of the fatigue crack growth in notched specimens under tension. The tests were performed on plane specimens with external blunt two-sided notches at room temperature. The tested material was O-TiAlNb titanium alloy. The tests were carried out at constant load value and constant stress ratio R = 0. The tests were done at the fatigue stand Instron under the loading change frequency of 25 Hz. The results of mechanical and structural tests of the examined alloy were presented. Scanning electron microscopy (SEM) was used in metallography, which allowed for the initial identification of intermetallic phases. The development of fatigue cracks in the tested alloy indicates that there is a tendency for brittle fracturing, which ran along the grain boundary.
本文给出了缺口试样在拉伸载荷下疲劳裂纹扩展的试验结果。试验在室温下对带有外部钝边双侧缺口的平面试样进行。试验材料为O-TiAlNb钛合金。试验在恒定载荷值和恒定应力比R = 0的条件下进行。试验在Instron疲劳试验机上以25Hz的加载变化频率完成。文中给出了所研究合金的力学和结构试验结果。金相分析采用扫描电子显微镜（SEM），这有助于对金属间相进行初步识别。试验合金中疲劳裂纹的扩展表明存在沿晶界脆性断裂的趋势。
