Effect of Boriding and Plasma Nitriding Process on Gamma Attenuation Parameters of Hardox 400 Alloy

In this study, the effect of boriding (BRD) and plasma nitriding (PN) processes on the radiation shielding properties of Hardox 400 was investigated. Gamma attenuation measurements were made in a good transmission geometry using a HPGe detector. A 133Ba radioactive source which emits photons 81 keV, 276 keV, 302 keV, 356 keV and 383 keV was used to irradiate the samples. Linear attenuation coefficients (LACs) of alloys were measured. The obtained LACs were then used to calculate the tenth value layers (TVLs), half value layers (HVLs) and mean free paths (MFPs) for the alloys. The results were compared with as received form of Hardox 400. It was concluded that single BRD processing decreases the LACs in all measured energies. In contrast to single processing, the dublex processing (BRD and PN) tends to increase the LACs of the materials. These changes are due to changes in electron density and effective atomic number of the Hardox 400 with BRD and PN processing. In order to fully understand the effects of the BRD and PN on LACs, the measurements should be taken at a wider energy range depending on the different functions of the BRD and PN processes.