3. A stress load of 10,000 psi is initially applied to a specimen held at 900°C….

3. A stress load of 10,000 psi is initially applied to a specimen held at 900°C. Due to a change in operation, the load is doubled but the strain rate in secondary creep has to remain unchanged for safety considerations. How much would the temperature need to be lowered? The activation is 35,000 cal/mol; the gas constant R = 1.987 cal/K-mol; and the strain-rate equation reads És = Kxo’exp ( R ) 120 points)