August 1, 2007
Conference Paper

Influence of carbon addition on neutron-induced void swelling of Fe-15Cr-16Ni-0.25Ti model alloy

Abstract

Addition of 0.05 wt% C to a model Fe-15Cr-16Ni-0.25Ti quaternary model alloy leads to a reduction in neutron-induced swelling at 400ºC. The transient regime of swelling is prolonged by carbon addition, most strongly at lower dpa rates. Contrary to the swelling behavior observed in carbon-free Fe-15Cr-16Ni and Fe-15Cr-16Ni-0.25Ti model alloys irradiated in the same experiment, Fe-15Cr-16Ti-0.25Ti-0.05C does not exhibit a strong dependence of swelling on dpa rate. It appears that carbon’s role, while not yet well-defined, operates via a solute-based or TiC complex mechanism rather than by a precipitate-based mechanism. A model is proposed whereby carbon stabilizes loop microstructures against unfaulting, where unfaulting is known to be a prerequisite to formation of the glissile dislocation network needed to establish a high swelling rate. This stabilization is proposed to counteract the tendency of loop unfaulting to occur more strongly at low dpa rates.

Revised: October 11, 2007 | Published: August 1, 2007

Citation

Sekimura N., T. Okita, and F.A. Garner. 2007. Influence of carbon addition on neutron-induced void swelling of Fe-15Cr-16Ni-0.25Ti model alloy. In Journal of Nuclear Materials, 367-370, 897-903. New York:Elsevier Science BV. PNNL-SA-53672. doi:10.1016/j.jnucmat.2007.03.065