Low cycle fatigue tests were conducted on the single crystal nickel-based superalloy, DD6, with different crystallographic orientations （i.e., [001], [011], and [111]） and strain dwell types （i.e, tensile, compress...Low cycle fatigue tests were conducted on the single crystal nickel-based superalloy, DD6, with different crystallographic orientations （i.e., [001], [011], and [111]） and strain dwell types （i.e, tensile, compressive, and balanced types） at a certain high temperature. Given the material anisotropy and mean stress, both orientation factor and stress range were introduced to the Smith, Watson, and Topper （SWT） stress model to predict the fatigue life. Experimental results indicated that the fatigue properties of DD6 depend on both crystallographic orientation and loading types. The fatigue life of the tensile, compressive, and balanced strain dwell tests are shorter than those of continuous cycling tests without strain dwell because of the important creep effect. The predicted results of the proposed modified SWT stress method agree well with the experimental data.展开更多
This work proposes two aspects about construction materials abased on Wenchuan post-earthquake investigations. According to different feature failure modes in various damaged structures and the cause of the damage to ...This work proposes two aspects about construction materials abased on Wenchuan post-earthquake investigations. According to different feature failure modes in various damaged structures and the cause of the damage to the effects of the loading during the ground motion, the structural failures were found related to low cycle fatigue (LCF) properties of building steel. The hitherto research development is presented briefly. The characters of cycle response of the steels are tested and discussed. During the post-earthquake reconstruction process, the disposal of huge quantities of earthquake demolition waste brought great challenges. Utilizing the waste concrete taken from earthquake-stricken area as recycled coarse aggregate (RCA) in the new concrete is conducted. Furthermore, the application perspective of RCA is discussed.展开更多
基金The financial support for this work from the National Natural Science Foundation of China （Grant No. 51341001） is appreciated.
文摘Low cycle fatigue tests were conducted on the single crystal nickel-based superalloy, DD6, with different crystallographic orientations （i.e., [001], [011], and [111]） and strain dwell types （i.e, tensile, compressive, and balanced types） at a certain high temperature. Given the material anisotropy and mean stress, both orientation factor and stress range were introduced to the Smith, Watson, and Topper （SWT） stress model to predict the fatigue life. Experimental results indicated that the fatigue properties of DD6 depend on both crystallographic orientation and loading types. The fatigue life of the tensile, compressive, and balanced strain dwell tests are shorter than those of continuous cycling tests without strain dwell because of the important creep effect. The predicted results of the proposed modified SWT stress method agree well with the experimental data.
文摘This work proposes two aspects about construction materials abased on Wenchuan post-earthquake investigations. According to different feature failure modes in various damaged structures and the cause of the damage to the effects of the loading during the ground motion, the structural failures were found related to low cycle fatigue (LCF) properties of building steel. The hitherto research development is presented briefly. The characters of cycle response of the steels are tested and discussed. During the post-earthquake reconstruction process, the disposal of huge quantities of earthquake demolition waste brought great challenges. Utilizing the waste concrete taken from earthquake-stricken area as recycled coarse aggregate (RCA) in the new concrete is conducted. Furthermore, the application perspective of RCA is discussed.
