Theory of the Thermal Breakaway of a Pinned Dislocation Line with Application to Damping Phenomena
Theory of the Thermal Breakaway of a Pinned Dislocation Line with Application to Damping Phenomena
复制标题
钉扎位错线热脱离理论及其在阻尼现象中的应用
DOI：
10.1063/1.1713074
复制
发表时间：
1964
期刊：
影响因子：
--
通讯作者：
K. Lücke
中科院分区：
文献类型：
--
作者：
L. Teutonico;A. Granato;K. Lücke
尽管Granato和Lucke关于含有位错的固体的应变-振幅-内摩擦和模量变化的力学理论给出了许多观察到的效应的公平解释，但简单的理论考虑表明，热波动的影响应该是非常重要的。为了将理论扩展到有限温度，需要详细研究作为外部应力函数的钉住位错线可能的静态平衡构型。这是在两个特定的例子中完成的，一个是单一钉钉点的位错，一个是连续钉钉剂的位错。一般地说明了如何从这些结果中计算阻尼和模量的变化，并对预期行为进行了定性讨论。对于高浓度的钉钉点，该理论同样适用于屈服点现象领域，并与前人的计算结果进行了比较。
Although the mechanical theory of Granato and Lucke for the strain‐amplitude‐dependent internal friction and modulus changes of solids containing dislocations gives a fair account of many of the observed effects, simple theoretical considerations show that the effect of thermal fluctuations should be very important. To extend the theory to finite temperatures, a detailed study of the possible static equilibrium configurations of a pinned dislocation line as a function of external stress is required. This is done here for the two specific examples of a dislocation with a single pinning point and a dislocation with a continuous pinning agent. It is shown in a general way how the damping and modulus change can be computed from these results, and a qualitative discussion of expected behavior is given. For high concentrations of pinning points, the theory is also applicable in the field of yield point phenomena, and the results found here are compared with previous calculations.