Evaluation of a Metal-Organic Composite (Tungsten-Lignin) for Attenuation of Gamma Radiation

• Published in: Materials research (São Carlos, São Paulo, Brazil) Vol. 22; no. suppl 1
• Main Authors: Souza, Armando Cirilo de, Cione, Francisco Carlos, Silva, Aline Cardoso da, Gouvêa, Adriana de Fátima Gomes, Machado, Noé Gabriel Pinheiro, Raele, Marcus Paulo, Rossi, Jesualdo Luiz
• Format: Journal Article
• Language: English
• Published: ABM, ABC, ABPol 01-01-2019; Associação Brasileira de Metalurgia e Materiais (ABM); Associação Brasileira de Cerâmica (ABC); Associação Brasileira de Polímeros (ABPol)
• Subjects: ENGINEERING, CHEMICAL; gamma radiation; lignin; MATERIALS SCIENCE, MULTIDISCIPLINARY; metal-organic composites; METALLURGY & METALLURGICAL ENGINEERING; tungsten; gamma radiation; lignin; tungsten; metal-organic composites
• ISSN: 1516-1439; 1980-5373; 1980-5373
• DOI: 10.1590/1980-5373-mr-2019-0045

The objective of this work was to use tungsten and lignin as precursors to obtain a metal-organic composite tungsten-lignin (W-Lig) using different sintering temperatures. Tungsten is a refractory metal and it was selected for the composite since it is widely used for high-energy radiation shielding as it has an excellent absorption cross section for thermal neutrons. Lignin extracted from lignocelluloses biomass and it was selected to be the organic precursor for the composite due to its multiple applications. Analysis of the composite was performed after sintering processes, using a 3D optical surface profiler and measurement of the gamma radiation attenuation coefficient using cobalt source (Co-60). Metal-organic composites in ratios of W2.5%Lig and W5%Lig (in mass % of lignin) were used. The gradient of the attenuation coefficient differed when standard tungsten and the composites of W2.5%Lig and W5%Lig were compared. Therefore, the attenuation coefficient between unobstructed free radiation and the W5%Lig 90 ºC composite showed a gradient of about 43% in the two characteristic Co-60 energy peaks, with a sample thickness of 0.679 cm the calculated linear attenuation coefficient was 0.832 cm-1.