真空热处理对钨中氘滞留行为的影响研究

Effect of Vacuum Heat Treatment on the Deuterium Retention Behavior in Tungsten

磁约束聚变装置真空室第一壁的烘烤处理温度一般不超过773 K,钨作为第一壁和偏滤器的重要候选材料,其氢同位素的热脱附温度常常高达800 K及以上。本研究通过气相热扩散方式向钨中引入氘,利用热脱附谱法(TDS)研究了真空热处理保温温度和时间对钨中氘脱附行为的影响。结果显示:对于未经真空热处理的钨,D_(2)的脱附峰对应温度为902 K,HD脱附峰为934 K;HD在1273 K以后仍存在热脱附峰。在经过了373~563 K真空热处理2 h后,钨中氘没有明显释放,但随热处理温度升高,D_(2)与HD峰位有向低温移动趋势;当热处理时间为3 h时,D_(2)与HD峰位向低温方向移动程度更大,且热处理温度提高至673 K时,在保温阶段即有大量氘释放,HD的第二个峰在1000 K以下即释放完毕。研究结果对于磁约束聚变装置真空室第一壁烘烤工艺的优化具有重要的参考意义。

The baking temperature of the first wall of the vacuum chamber of magnetic confinement fusion device generally does not exceed 773 K.However,as an important candidate material for the first wall and divertor,the thermal desorption temperature of hydrogen isotopes in tungsten is often as high as 800 K or above.In this work,deuterium was introduced into tungsten by gas phase thermal diffusion,and the effect of vacuum heat treatment holding temperature and time on deuterium desorption behavior in tungsten was studied by thermal desorption spectroscopy(TDS).The results show that for tungsten without vacuum heat treatment,the corresponding temperature of D_(2)desorption peak is 902 K and HD desorption peak is 934 K.There is still a thermal desorption peak of HD after 1273 K.After vacuum heat treatment at 373~563 K for 2 h,deuterium in tungsten is not released obviously,but with the increase of heat treatment temperature,D_(2)and HD peaks tend to move to low temperature.When the heat treatment time is 3 h,the peaks of D_(2)and HD move to the low temperature direction more,and when the heat treatment temperature is increased to 673 K,a large amount of deuterium is released in the heat preservation stage,and the second peak of HD is released below 1000 K.The results have positive reference significance for optimizing the baking process of the first wall of the vacuum chamber of the magnetic confinement fusion device.