摘要
研究了高Co-Ni钢单边缺口三点弯曲试样在变幅冲击疲劳载荷下的裂纹扩展行为。结果表明,从高能变载到低能时,裂纹扩展a-N曲线出现迟滞平台,裂纹扩展速率出现迟滞;迟滞延长寿命△N与变幅能量差△A间呈幂函数关系;裂纹扩展出现迟滞与裂纹尖端闭合效应有关。从低能变载到高能后,扩展速率按对应能量恒幅冲击时的扩展速率扩展。
The crack growth behavior of single-edge notched specimens of high Co-Ni steel using three-point bend impact fatigue method under non-constant energy was studied. The results show that there is a platform on the a-N curve while the impact energy changes from high-energy into low-energy, and the crack growth rate degreases greatly. The hysteresis life AN is power function increasing with non-constant impact energy difference AA. The hysteresis effect is related with crack closure effect. When the impact energy changes from low-energy into high -energy, the crack growth rate is equal with constant amplitude imoact under correspond energy.
出处
《热加工工艺》
CSCD
北大核心
2014年第4期88-90,共3页
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