EFFECT OF GRAIN DIAMETER ON THE TRANSIENT CREEP CHARACTERISTICS OF CU-10 WT-PERCENT SN ALLOY

Specimens of different grain diameters were prepared from Cu-10 wt% Sn alloy and creep tests were carried out under different stresses and at different temperatures corresponding to alpha-solid solution of the material. It was found that at a given temperature, the transient creep parameter n decreased with a higher rate for fine-grained specimens than for coarse-grained ones. The parameter B was found to increase linearly with grain diameter. The results yielded an activation energy of 0.43 eV which is in good agreement with grain boundary sliding or migration. The dependence of the steady strain rate on the transient creep parameter B proved to be valid with the exponent lambda depending on the stress.