Creep of Copper at Intermediate Temperatures
Tóm tắt
Activation energies for creep of copper at intermediate temperatures, where crystal recovery was negligible, were determined by the simple technique of rapidly alternating the test temperature between T1 and T2 (T2= T1 + about 10°K) throughout a constant stress creep test. The activation energy for creep ΔH was found to be 37,000 ± 3,000 cal per mol, independent of stress and strain. The same creep laws as have been previously established for high temperature creep were found to be valid for creep at intermediate temperatures. But the ΔH was found to be lower than that for self-diffusion in the intermediate temperature range whereas it is known to be equal to that for self-diffusion at high temperatures.
Tài liệu tham khảo
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