Assessment of exposure buildup factors of some oxide dispersion strengthened steels applied in modern nuclear engineering and designs

• We report new data on energy absorption and exposure buildup factor for some oxide dispersion strengthened steels.
• The GP fitting method can be used to calculate buildup factors up to 40 mfp.
• These parameters are useful in reactor and to its structural shielding materials.

The gamma-ray exposure buildup factors of oxide dispersive-strengthen (ODS) steel alloys have been computed for photon energy 0.015–15 MeV up to 40 mean free path (mfp) penetration depth by geometrical progression (GP) method. An appreciable variation in exposure buildup factors for the investigated ODS steel alloys was observed. The exposure buildup factors of ODS alloys were observed strongly depending upon the photon energy, penetration depths and the chemical compositions. The exposure buildup factors were found to be small in low- and high-photon energy whereas these were very large in intermediate-energy region. Our investigation signifies that the Eurofer 97 ODS steel alloy is the superior gamma-ray and neutron shielding materials. This study should be useful for shielding design and application in future reactor technologies and fusion reactor blankets.