CREEP BEHAVIOR OF Zr-1.5Nb-0.4Sn-0.1Fe-0.1Cu ALLOY

Creep behavior of the Zr-1.5Nb-0.4Sn-0.1Fe-0.1Cu alloy sheet is investigated from 300℃ to 400℃ in the stress range from 50 MPa to 180 MPa along the rolling direction.The measured strain rates range from 8.8 ×10-10 s-1 to 4.7×10-7 s-1.The activation energies are estimated to assess the creep deformation mechanisms in this alloy.The strain rate is slightly different at low stress,while it shows a distinct difference at high stresses.Stress exponents of this alloy increase with increasing applied stress at all testing temperatures.It is concluded that the creep deformation of the Zr-1.5Nb-0.4Sn-0.1Fe-0.1Cu alloy is controlled by the diffusion creep at low stress region and by the climbing of dislocations at high stress region.