Experimental study of consistency degradation of different greases in mixed neutron and gamma radiation

• DOI: 10.1016/j.heliyon.2019.e02489
• Publication Date: 2019-09-25T12:33:12Z
• Authors: Matteo Ferrari; Aldo Zenoni; Monika Hartl; Yongjoong Lee; Alberto Andrighetto; Alberto Monetti; Andrea Salvini; Fabio Zelaschi
• Keywords: TRIGA; Neutron radiation; Radiation Resistance; radiation damage

Many of the moving components in accelerator and target environments require lubrication. Lubricants such are exposed to high fluxes secondary radiation, which originates from beam interactions with losses. The radiation is a mix components, can include significant fractions neutrons. radiation-sensitive polymeric materials. radiation-induced modifications their structure reduce service lifetime impose additional facility maintenance, complicated by environmental radioactivity. study lubricants resistance therefore necessary for construction new generation accelerators systems. Nevertheless, data collected mixed fields scarce. Nine commercial greases were irradiated at TRIGA Mark II Research Reactor serve projects like European Spallation Source (ESS) Lund (Sweden) Selective Production Exotic Species (SPES) Legnaro, (Italy). Mixed neutron gamma doses ranging 0.1 MGy 9.0 delivered greases. For an experimental quantification degradation, consistency was measured. Two remained stable, while others became fluid. Post-irradiation examinations evidence cleavage as dominant effect. Dose fluence limits use each product presented. Apart scientific significance, results represent original useful reference selecting resistant applications.