摘要: |
通过对涡轮叶片用、定向凝固合金材料DZ4紧凑拉伸试样的断裂韧性计算,在有限元程序MSC.MARC下建立了复杂构件应力强度因子的计算模型;结合试验研究,计算了预置裂纹叶片的应力强度因子,分析了发生断裂时的状态,发现叶片的断裂韧性具有较大的分散性,其中一部分明显低于材料的试验值;对工作条件下的故障叶片进行了模拟计算,反映出该叶片在发生断裂时瞬断区偏大而疲劳区偏小的断裂特征。 |
关键词: 航空发动机 涡轮叶片 定向凝固 断裂韧性+ 应力强度因子 |
DOI: |
分类号:V250.2 |
基金项目: |
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Analysis for fracture characteristic of pre-cracked directionally solidified turbine blades |
WEI Da-sheng1, WANG Yan-rong2, LI Wei3
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1.Coll.of Energy and Power Engineering,Beijing Univ.of Aeronautics and Astronautics,Beijing 100083,China;2.Coll.of Energy and Power Engineering,Beijing Univ.of Aeronautics and Astronautics,Beijing 100084,China;3.The First Inst.Air Force,Beijing 100076,China
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Abstract: |
Based on the numerical simulation of fracture toughness of the compact tensile(CT) specimen,a numerical model for the stress intensity factor of turbine blades was established by use of MSC.MARC software.The stress intensity factor of pre-cracked turbine blades was evaluated for the fracture state of blades.The fracture toughness of blades shows great scatter, and some of them are remarkably lower than that obtained in material testing.The simulation results of failure blade under operating condition show that the characteristic in fracture section,i.e.the area of fatigue zone is small while that of the instantaneous fracture zone is large. |
Key words: Aircraft engine Turbine blade Directional solidification Fracture toughness+ Stress-intensity factor |