Influence of the Field and the Current Limit on Flash Sintering at Isothermal Furnace Temperatures
Influence of the Field and the Current Limit on Flash Sintering at Isothermal Furnace Temperatures
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DOI：
10.1111/jace.12472
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发表时间：
2013-09
影响因子：
3.9
通讯作者：
J. Francis;R. Raj
中科院分区：
文献类型：
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作者：
J. Francis;R. Raj
我们报告，第一次，观察的保温时间的实验中进行的等温炉温度的闪速烧结的发病。孵化时间随着DC场的强度高度非线性地变化，类似于成核现象。电源最大电流的设置对致密化程度有显著影响。在这些电流设置下的保持时间对晶粒尺寸有影响，晶粒尺寸随着时间和电流设置的大小而增加。实验在3摩尔%氧化钇稳定的氧化锆上进行。在所有情况下，从先前验证的黑体辐射模型估计的闪速烧结过程中的试样温度仍然远低于氧化钇稳定的氧化锆的常规烧结所需的温度。总之，这些观察结果意味着一个成核的缺陷雪崩作为一个可能的机制闪光烧结。
We report, for the first time, the observation of an incubation time for the onset of flash sintering in experiments carried out at isothermal furnace temperatures. The incubation time varies highly nonlinearly with the strength of the DC field, akin to a nucleation-like phenomenon. The setting of the maximum current at the power supply has a significant influence on the extent of densification. The hold time at these current settings has an influence on the grain size increasing it with time and the magnitude of the current setting. The experiments were carried out on 3 mol% yttria-stabilized zirconia. In all instances the specimen temperatures during flash sintering, estimated from a previously validated blackbody radiation model remain well below the temperatures that would be required for conventional sintering of yttria-stabilized zirconia. Taken together these observations imply a nucleation of defect avalanche as a possible mechanism for flash sintering.