Abstract Stress reduction creep tests conducted on a Cu-Cr-Nb alloy (GRCop-84) at 923 K have confirmed local dislocation climb to be the rate-controlling deformation mechanism. The activation energy of creep was measured to be consistent with that of self-diffusion in Cu matrix. An internal back stress of approximately -9 MPa was identified to act on the rate-controlling dislocations, which is believed to be the sum of the back stress for dislocation-particle interaction and the forward stress for dislocation-dislocation interaction. This back stress, however, does not lead to a true threshold in the framework of thermally activated dislocation motion.

中文翻译：

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通过在恒定结构条件下进行测试了解 Cu-Cr-Nb 合金的蠕变机制

摘要 在 923 K 下对 Cu-Cr-Nb 合金 (GRCop-84) 进行的应力降低蠕变试验已证实局部位错爬升是速率控制变形机制。测量蠕变的活化能与铜基体中的自扩散的活化能一致。确定了大约 -9 MPa 的内部背应力作用于控制速率的位错，这被认为是位错-粒子相互作用的背应力和位错-位错相互作用的前向应力的总和。然而，这种背应力不会导致热激活位错运动框架中的真正阈值。