ANOMALOUSLY AMPLITUDE DEPENDENT EFFECT OF THE LOW-TEMPERATURE INTERNAL-FRICTION PEAKS IN COLD-WORKED DILUTE ALUMINIUM-COPPER SOLID SOLUTION

The composite internal friction peak (versus temperature) assumed to be consisted of a relaxation peak and a phase transformation peak previously observed in cold-worked Al-0.50wt% (0.21at%) Cu at temperatures below room temperature are now resolved into two separate peaks. Internal friotion peaks as a function of strain amplitude (the amplitude peak) are observed around the temperature region of both peaks for he first time.