The velocity of edge dislocations in 99.999% pure copper crystals has been measured as a function of stress at temperatures from 66°K to 373°K by means of a torsion technique. The range of resolved shear stress was 0 to 15 megadynes/cm^2 for seven temperatures (66°K, 74°K, 83°K, 123°K, 173°K, 296°K, 373°K).ududDislocation mobility is characterized by two distinct features: (a) relatively high velocity at low stress (maximum velocities of about 9000 cm/see were realized at low temperatures), and (b) increasing velocity with decreasing temperature at constant stress.ududThe relation between dislocation velocity and resolved shear stress is: ududv=v_0(τ_r)/τ_0)^n, ududwhere v is the dislocation velocity at resolved shear stress τ_r, v_o is a constant velocity chosen equal to 2000 cm/sec, τ_0 is the resolved shear stress required to maintain velocity v_0, and n is the mobility coefficient. The experimental results indicate that τ_0 decreases from 16.3 × 10^6 to 3.3 × 10^6 dynes/cm^2 and n increases from about 0.9 to 1.1 as the temperature is lowered from 296°K to 66°K.udThe experimental dislocation behaviour is qualitatively consistent with an interpretation on the basis of phonon drag.
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机译：已经通过扭转技术测量了在66°K至373°K的温度下，99.999％纯铜晶体中边缘位错的速度与应力的关系。七个温度（66°K，74°K，83°K，123°K，173°K，296°K，373°K）的解析剪切应力范围为0至15兆达因/厘米^ 2。 ud位错迁移率具有两个明显的特征：（a）在低应力下具有相对较高的速度（在低温下可实现约9000 cm / see的最大速度），以及（b）在恒定应力下随着温度的降低而增加速度。 ud位错速度和解析剪切应力之间的关系为： ud udv = v_0（τ_r）/τ_0）^ n， ud ud其中v是解析切应力τ_r时的位错速度，v_o是一个恒定速度，等于2000 cm / sec，τ_0是维持速度v_0所需的分解剪切应力，n是迁移率系数。实验结果表明，随着温度从296°K降至66°K，τ_0从16.3×10 ^ 6达因/ cm ^ 2降低至3.3×10 ^ 6达因/ cm ^ 2，n从约0.9升高至1.1。该行为与基于声子阻力的解释在质量上是一致的。
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