Creep of heat resistant steel.

The primary and steady-state creep behavior of 310 stainless steel has been investigated over the temperature range 500$\sp\circ$C to 700$\sp\circ$C (0.46-0.58T$\sb{\rm m}$). The steady state stress exponent increased slightly with increasing grain size. The activation energy for steady state creep determined at $\sigma$ = 300 MPa, d = 40 $\mu$m, Q$\sb{\rm c}$ = 250 KJ/mol, is approximately that for the volume self-diffusion of iron (280 KJ/mol). Also the activation energy determined for primary creep is almost the same as that for secondary creep. The grain diameter parameter, m, (in equation $\dot\varepsilon\sb{\rm c}$ = A $\sigma\sp{\rm n}$ d$\sp{\rm m}$ exp (-Q$\sb{\rm c}$/RT)) was determined to be $-$1.67 for $\sigma$ = 300 MPa and T = 600$\sp\circ$C. For 310 stainless steel, constitutive equations have been developed to describe both the primary and secondary creep behavior. The effect of second phase-carbides on the microstructure and high temperature mechanical properties was determined for experimental alloys of the HP-Nb type (Fe-35Ni-25Cr-1Nb) in both the as-cast condition and aged at 1100$\sp\circ$C condition. (Abstract shortened by UMI.)Dept. of Mechanical, Automotive, and Materials Engineering. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1991 .W342. Source: Masters Abstracts International, Volume: 31-01, page: 0414. Thesis (M.A.Sc.)--University of Windsor (Canada), 1991