Stored energy measurements in copper single crystals tensile deformed at 20°C

Abstract

Copper single crystals (99.999 per cent purity) of orientations near 〈110〉, 〈111〉, 〈311〉 and 〈322〉 have been tensile deformed at room temperature to different shear stresses within stage III. The energy stored in these crystals has been measured by heating them within an adiabatic twin calorimeter of high precision to temperatures above recrystallization. No stored energy release was observed below the recrystallization temperature. The stored energies measured during recrysatllization temperature. The stored energies measured during recrystallization were smaller by a factor of two or more than comparable data obtained by deformation calorimetry. The stored energy increased with the square of the shear stress for crystals deformed up to shear stresses of about 8 kp/mm 2. The ratio of stored energy to expended work amounted to about 6 per cent.