Investigation of thermal expansion measurement of brass strip H62 after high current density electropulsing by the CCD technique

The elongation delta of a brass strip (H62) was greatly improved after high current density electropulsing treatment. The thermal expansion (Delta L/L-0) of the brass strip samples with different treatment conditions has been measured by the CCD (charge coupled device) technique in the temperature range from 20 to 250 degrees C. The results show that delta and Delta L/L-0 reveal almost similar variation for different treatment conditions. By the observation of transmission electron microscopy of the brass strip and the in-situ detection of current waveform during electropulsing, the probable mechanism of property variations of the brass strip has been discussed. (C) 2000 Elsevier Science S.A. All rights reserved.