TEM analysis of proton irradiated mixed phase steel

Electron-based microanalytical analysis of proton irradiated 308L weldment groove filler material has been performed as part of a LWR sustainability project sponsored by the US DOE NEUP.   Some of this work has been published [308L irradiated microstructures].

 

Tensile specimen loaded onto the load frame grips for autoclave immersion testing.

EDS mapping of various elements associated with primary and secondary cracks in 308L stainless steel weldment groove filler material.  This material was proton irradiated at the University of Michigan to approximately 5 dpa.  The slow strain rate immersion testing was done under BWR normal water chemistry conditions (approximately 2000 ppb dissolved oxygen) to promote corrosive attack.  The sample was strained to approximately 5%.   The EDS demonstrate that oxides form as cracks propagate along delta-gamma phase boundaries in the dual phase 308L material.