Behaviour of hardening and serration yield of a Fe-Ni-Cr alloy under isothermal cycling （ISC） and out-phase TMF was studied on the basis of varied hysteresis loops. Cycling hardening and serrated yielding for ISC de...Behaviour of hardening and serration yield of a Fe-Ni-Cr alloy under isothermal cycling （ISC） and out-phase TMF was studied on the basis of varied hysteresis loops. Cycling hardening and serrated yielding for ISC depend on the temperature and the total strain range, stronger hardening with serrated yielding at higher strain range under ISC at 600 ℃, but no hardening and serrated yielding occurred under ISC at 800 ℃. Stronger hardening with stress serration occurred at the thermal path going to the lowest temperature, no stress serration occurred at the highest temperature under the out-phase. The hardening also depends on the total strain range, higher total strain range with lower cycling temperature resulted in a stronger hardening and remarkable serration yielding behavior. Weaker hardening without serrated yielding occurred at near 800℃ may due to an obvious cycling stress drop under out-phase TMF. Change in the shape of the hysteresis loops also expresses the degree of the damage of the tested alloy under out-phase and ISC.展开更多
The influences of out-phase electromagnetic field on the as-cast structure of horizontal direct chill casting aluminum alloy ingot were experimental by and numerical by studied. The results of numerical analysis show ...The influences of out-phase electromagnetic field on the as-cast structure of horizontal direct chill casting aluminum alloy ingot were experimental by and numerical by studied. The results of numerical analysis show that the interaction of the out-phase electromagnetic field and the melt can generate an electromagnetically induced forced flow in the melt, which, in turn, changes flow pattern and temperature field in the mold. The as-cast structure of the ingot can be greatly improved by the changes of flow pattern and temperature field. The results of experimental analysis show that with application of out-phase electromagnetic field, temperature distribution in the melt is more uniform, grain morphology changes from columnar grains to equiaxed grains and grain size decreases.展开更多
文摘Behaviour of hardening and serration yield of a Fe-Ni-Cr alloy under isothermal cycling （ISC） and out-phase TMF was studied on the basis of varied hysteresis loops. Cycling hardening and serrated yielding for ISC depend on the temperature and the total strain range, stronger hardening with serrated yielding at higher strain range under ISC at 600 ℃, but no hardening and serrated yielding occurred under ISC at 800 ℃. Stronger hardening with stress serration occurred at the thermal path going to the lowest temperature, no stress serration occurred at the highest temperature under the out-phase. The hardening also depends on the total strain range, higher total strain range with lower cycling temperature resulted in a stronger hardening and remarkable serration yielding behavior. Weaker hardening without serrated yielding occurred at near 800℃ may due to an obvious cycling stress drop under out-phase TMF. Change in the shape of the hysteresis loops also expresses the degree of the damage of the tested alloy under out-phase and ISC.
基金Supported by Postdoctor Fund of Northeastern University
文摘The influences of out-phase electromagnetic field on the as-cast structure of horizontal direct chill casting aluminum alloy ingot were experimental by and numerical by studied. The results of numerical analysis show that the interaction of the out-phase electromagnetic field and the melt can generate an electromagnetically induced forced flow in the melt, which, in turn, changes flow pattern and temperature field in the mold. The as-cast structure of the ingot can be greatly improved by the changes of flow pattern and temperature field. The results of experimental analysis show that with application of out-phase electromagnetic field, temperature distribution in the melt is more uniform, grain morphology changes from columnar grains to equiaxed grains and grain size decreases.
