abstract
Using the impression test, the effect of electric current on the creep deformation of Pb was studied in the
temperature range of 343–403 K and under the punching stress of 11.1–30.5 MPa. During the impression
test of constant load, a direct electric current in a range of 0–5 A passed through the punch into the Pb-sample. A steady state creep with sudden jumps in the impression curves was observed. A power–law
relation was used to describe the dependence of the steady state impression velocity on the punching
stress. The average stress exponent increased from 3.2 to 4.0 with increasing electric current and the
apparent activation energy was 36.0 kJ/mol for small punching stresses. For large punching stresses, the
average stress exponent decreased with increasing electric current and the apparent activation energy
decreased from 63.5 kJ/mol to 49.7 kJ/mol with increasing electric current from 0 to 5 A