Mechanical properties of two chromium alloys in as-received and heat-treated conditions

The main attractions of chromium alloys for fusion applications are their high corrosion resistance and low activation properties. For the improvement of mechanical strength properties, these materials use oxide dispersion strengthening (ODS). The main drawbacks are low impact fracture toughness up to 1150 K, coupled with limitations in welding, shaping and other manufacturing processes. This paper describes the work performed in 1999 by SCK-CEN for the European Fusion Programme, in order to obtain exploratory results for the assessment of the possible use of such materials in a reactor concept. Tensile, instrumented impact and static three-point bend tests have been carried out on two fine-structured alloys, denominated DUCROPUR (99.97% pure Cr) and DUCROLLOY, an oxide dispersion strengthened alloy (Cr–5%Fe–1%Y2O3), in as-HIPped and heat-treated conditions. Some tensile tests have also been carried out on specimens irradiated at 300 °C to approximately 0.5 dpa.