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前文結果指出,用扭摆作內耗測量,观察到钼中含氧和含氮分别引起两个內耗峯(氧的两个內耗峯分别在115℃和200℃附近,氮的两个內耗峯分别在160℃和300℃附近)。本文进一步証实这些內耗峯分别是由氧和氮間隙原子的应力感生微扩散所引起的。 对于含氧的內耗峯作了比較系統的試驗,結果指出,115℃附近的內耗峯的高度与固溶体中含氧量成正比,200℃附近的內耗峯的高度与固溶体中含氧量的平方成比例。对于上述这两个含氧內耗峯所測得的激活能分别等于25,200卡/克分子和30,000卡/克分子,含氮的160℃的內耗峯的激活能为28,500卡/克分子。从以上的結果分析,可以认为,115℃和160℃附近的內耗峯分别是自由的、无交互作用的氧和氮原子的应力感生扩散引起的,200℃的內耗峯与氧原子对的交互作用有关。 从激活能值和計算的扩散常数之間的关系,可以得到氧和氮在钼中的理論扩散系数。

Additional evidence is presented to prove that the two internal friction peaks associated with the presence of either oxygen or nitrogen in molybdenum previously observed by internal friction measurements with a torsion pendulum (two internal friction peaks of oxygen occurred at temperatures around 115℃ and 200℃, whereas, two of nitrogen were observed at 160℃ and 300℃ respectively) are associated with the stress-induced micro-diffusion of oxygen and nitrogen in molybdenum.Systematic investigations have been carried out to study the nature of the internal friction peaks of oxygen. The results showed that the height of the internal friction peak at 115℃ is proportional to the oxygen content in solid solution, while the height of the other internal friction peak at 200℃ is a quadratic function of the oxygen content in solid solution. The activation energies for diffusion were found to be 25.2 kcal/mole and 30 kcal/mole for the two oxygen peaks, for the nitrogen peak at 160℃ the corresponding activation energy was found to be 28.5 kcal/mole.From the above results, it is believed that the 115℃ peak may arise from the diffusion of free non-interacting interstitial oxygen, whereas, the 200℃ peak may be correlated with the diffusion of oxygen atoms each of which interacts with another oxygen atom in its neighbourhood.Theoretical diffusion coefficient curves for these systems were also obtained from the relationship between activation energies and the calculated diffusion coefficient constant.