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In this study, 1010, 1040, 1050 and 1090 carbonized steels were investigated against gamma radioisotope sources on their gamma attenuation properties. Co-60, Cs-137 and Ir-192 gamma radioisotopes which are commonly used in industrial applications were used in the experiments. Half-value layers were carried out for studied carbonized steels against all studied gamma radioisotopes. In addition, the linear and mass attenuation coeffcients were determined for each carbonized steels at different gamma radioisotope sources. The theoretical mass attenuation coeffcients were calculated from XCOM computer code for all samples at specific energies of Co-60, Cs-137 and Ir-192 gamma sources. The theoretical and experimental results were compared with each other. [ABSTRACT FROM AUTHOR]

In this study gamma and neutron attenuation properties of boron carbide–aluminium (B4C–Al) composites were investigated. B4C–Al composites were produced by spark plasma sintering method. Aluminum percentages in the B4C–Al composites were 0%, 10%, 15%, and 20% by volume. The composite materials were performed against gamma and neutron sources. Cs-137 and Co-60 gamma radioisotopes were used as gamma sources and Pu–Be neutron howitzer was used for neutron source. Theoretical mass attenuation coefficients were determined by using XCOM computer code and compared with the experimental results. It has been seen that the experimental results were close to the theoretical results. Total macroscopic cross-sections of the samples were determined for Pu–Be neutrons. It is concluded that increasing aluminum ratio in the B4C–Al composites causes higher gamma attenuation behavior for Cs-137 and Co-60 gamma sources and the total macroscopic cross-sections of the B4C–Al composites decrease by increasing Al concentration. [ABSTRACT FROM AUTHOR]

According to RoHS (Restriction of Hazardous Substances) directive of European Union it is restricted using lead in many equipment and applications. It is possible to enlarge the restriction of lead usage in some other applications which is including some of nuclear applications in the future. Therefore new materials or systems need to be developed instead of lead as radiation shielding materials and/or collimators. In this study pure tungsten, tungsten carbide-cobalt (WC-Co) materials were investigated against gamma radiation. For gamma radiation Cs-137 and Co-60 gamma radioisotope sources were used. The linear and mass attenuations were calculated. The experimental results were compared with XCOM computer code. Usage possibilities of WC-Co instead of lead in nuclear applications as gamma shielding material were discussed. It has been investigated that the linear gamma attenuation coefficients of lead and WC-Co are very close to each other. Therefore it could be said that WC-Co materials is an alternative promising material which could be used instead of lead as gamma shielding material and/or collimator. [ABSTRACT FROM AUTHOR]

Boron carbide is a material which has wide application areas in industry including nuclear technology. Titanium diboride–boron carbide composites which were produced from different boron carbide particle sizes were studied for searching of the behaviour against the gamma ray. Micron size and submicron size boron carbide were used to produce composite materials. The volume of boron carbide and titanium diboride in the composites are 85% and 15%, respectively. For the investigation of the gamma radiation behaviour of these materials, Cs-137 radioisotope was used as gamma source in the experiments which has a single gamma-peak at 0.662 MeV. Gamma transmission technique was used for the measurements. The effects of boron carbide particle size on radiation attenuation of titanium diboride–boron carbide composites were evaluated in relation with gamma transmission and the results of the experiments were interpreted and compared with each other. It could be understood that decrease of particle size of boron carbide in boron carbide–titanium diboride composites causes higher linear and mass attenuation coefficient values. So, submicron size boron carbide used composite materials are more convenient than micron size boron carbide used composite materials as radiation shielding materials for nuclear applications. [ABSTRACT FROM AUTHOR]