Experimental Assessments of Notch Ductility and Tensile Strength of Stainless Steel Weldments after 120 deg C Neutron Irradiation

摘要

The Charpy-V (C/sub v/) properties of AISI 300 series stainless steel plate, weld, and weld heat-affected zone (HAZ) materials from commercial production weldments in 406-mm-diameter pipe (12.7-mm wall) were investigated in unirradiated and irradiated conditions. Weld and HAZ tensile properties were also assessed in the two conditions. The plates and weld filler wires represent different steel melts; the welds were produced using the multipass MIG process. Weldment properties in two test orientations were evaluated. Specimens were irradiated in the UBR reactor to 1 x 10 sup 20 n/cm sup 2 , E >0.1 MeV in a controlled temperature assembly. Specimen tests were performed at 25 deg C and 125 deg C. The radiation-induced reductions in C/sub v/ energy absorption at 25 deg C were about 42 percent for the weld and HAZ materials evaluated. A trend of energy increase with temperature was observed. The concomitant elevation in yield strength was about 53%. In contrast, the increase in tensile strength was only 16%. The postirradiation yield strength of the axial test orientation in the pipe was less than that of the circumferential test orientation. Results for the HAZ indicate that this component may be the weakest link in the weldment from a fracture resistant viewpoint. (ERA citation 11:054136)