Huaihe River Basin Energy and Water Cycle Ex-periment and Research (HUBEX), as one of the Ninth Five-Year Plan (1996-2000) Major Programs support-ed by the National Natural Science Foundation of China(NSFC), successfu...Huaihe River Basin Energy and Water Cycle Ex-periment and Research (HUBEX), as one of the Ninth Five-Year Plan (1996-2000) Major Programs support-ed by the National Natural Science Foundation of China(NSFC), successfully passed the check-up and won high appraisement from the experts. Huaihe River Basin, located in the inland of the eastern Asia monsoon area, is the key base for rice-cotton production and suf-fers from the frequent drought and flood. In order to in-vestigate the climate problem of Huaihe River Basin area,展开更多
The fatigue and fracture behavior of nickel-based superalloy Inconel 718 was investigated up to the very high cycle regime under rotary bending tests at room temperature. It was found that this superalloy can still fr...The fatigue and fracture behavior of nickel-based superalloy Inconel 718 was investigated up to the very high cycle regime under rotary bending tests at room temperature. It was found that this superalloy can still fracture after exceeding 107 cycles. Fractographic analysis revealed that there was a transition from fatigue crack initiation at multi-sites to single initiation with decreasing stress levels. The fracture surface can be divided into four areas according to the appearance, associated with fracture mechanics analysis of the corresponding stress intensity factors. The fracture mechanism dominant in each area was disclosed by scanning electron microscope examination and analyzed in comparison with those obtained from the crack growth tests. Subsequently, life prediction modeling was proposed by estimating the crack initiation and propagation stage respectively. It was found that Chan (2003)'s model for initiation life and the Paris law for growth life can provide comparable predictions against the experimental life.展开更多
文摘Huaihe River Basin Energy and Water Cycle Ex-periment and Research (HUBEX), as one of the Ninth Five-Year Plan (1996-2000) Major Programs support-ed by the National Natural Science Foundation of China(NSFC), successfully passed the check-up and won high appraisement from the experts. Huaihe River Basin, located in the inland of the eastern Asia monsoon area, is the key base for rice-cotton production and suf-fers from the frequent drought and flood. In order to in-vestigate the climate problem of Huaihe River Basin area,
基金Project supported by the National Natural Science Foundation of China (Nos 10872105 and 51071094)the Mitsubishi Heavy Industries, Ltd, Japan
文摘The fatigue and fracture behavior of nickel-based superalloy Inconel 718 was investigated up to the very high cycle regime under rotary bending tests at room temperature. It was found that this superalloy can still fracture after exceeding 107 cycles. Fractographic analysis revealed that there was a transition from fatigue crack initiation at multi-sites to single initiation with decreasing stress levels. The fracture surface can be divided into four areas according to the appearance, associated with fracture mechanics analysis of the corresponding stress intensity factors. The fracture mechanism dominant in each area was disclosed by scanning electron microscope examination and analyzed in comparison with those obtained from the crack growth tests. Subsequently, life prediction modeling was proposed by estimating the crack initiation and propagation stage respectively. It was found that Chan (2003)'s model for initiation life and the Paris law for growth life can provide comparable predictions against the experimental life.
