Following the pressurization-to-failure testing of the PM-2A reactor pressure vessel, several sections of steel were removed from the vessel wall in a region adjacent to the artificial defect. Charpy V-notch and tension test specimens machined from one of these sections were evaluated. The irradiated-condition 30 ft-lb transition temperatures for the 1/4 thickness (nearest to the core) and 3/4 thickness locations in the vessel wall were +115 and +55 F, respectively, for measured fission spectrum fluences of 7.3 and 4.0 × 10¹⁸ n/cm² ⟩1 MeV. The 1/4 thickness properties and fluence most nearly represented those at the tip of the artificial defect. The 0.2 percent yield strength for the 1/4 thickness location was 97,620 psi at -20 F (failure temperature) and 92,200 psi at +72 F (temperature at time of acid sharpening treatment of artificial defect). Significant uniform elongation, reduction of area, and elongation in 1 in. were retained by the steel. An assessment of the stress, temperature, and flaw size conditions for the PM-2A failure, as indexed by the irradiated-condition mechanical properties, indicates that the failure is in agreement with the generalized fracture analysis diagram.