NSUF 17-1090: In situ amorphization studies of forsterite, diopside and quartz under ion irradiation

The proposed project objectives are to redefine the critical ion doses for amorphization of forsterite, diopside and quartz, and to study the amorphization kinetics using four different temperatures for irradiation. The use of the IVEM-Tandem facilities at Argonne National Laboratory is requested to irradiate the samples with an ion beam and perform in-situ TEM studies. The obtained set of data will be very novel, since these systems have never been irradiated under in-situ TEM characterization. These silicates are often present in concrete aggregates, therefore, their response to irradiation is of interest to study the stability of the concrete bio-shield in nuclear power plants. They are known to expand with irradiation and amorphization, which has a negative impact on the mechanical properties of concrete, due to swelling and cracking. These experiments will be a first approach to obtain amorphous fractions with ion doses taking SAED patterns. These data will serve to inform mechanical models that predict the degradation of cement and concrete with neutron irradiation. The damage profiles for a certain amorphous fraction will be correlated to equivalent neutron doses, and coupled to the respective volumetric expansion. A further set of experiments will be carried out in the future to obtain the volumetric expansion of thin sections of these minerals irradiated at the same doses chosen to take the SAED patterns. The samples for the in-situ investigations are already available, and the experiments will be finished in a session of 5 days.

Additional Info

Field	Value
Abstract	The proposed project objectives are to redefine the critical ion doses for amorphization of forsterite, diopside and quartz, and to study the amorphization kinetics using four different temperatures for irradiation. The use of the IVEM-Tandem facilities at Argonne National Laboratory is requested to irradiate the samples with an ion beam and perform in-situ TEM studies. The obtained set of data will be very novel, since these systems have never been irradiated under in-situ TEM characterization. These silicates are often present in concrete aggregates, therefore, their response to irradiation is of interest to study the stability of the concrete bio-shield in nuclear power plants. They are known to expand with irradiation and amorphization, which has a negative impact on the mechanical properties of concrete, due to swelling and cracking. These experiments will be a first approach to obtain amorphous fractions with ion doses taking SAED patterns. These data will serve to inform mechanical models that predict the degradation of cement and concrete with neutron irradiation. The damage profiles for a certain amorphous fraction will be correlated to equivalent neutron doses, and coupled to the respective volumetric expansion. A further set of experiments will be carried out in the future to obtain the volumetric expansion of thin sections of these minerals irradiated at the same doses chosen to take the SAED patterns. The samples for the in-situ investigations are already available, and the experiments will be finished in a session of 5 days.
Award Announced Date	2017-09-20T12:35:25.977
Awarded Institution	None
Facility	None
Facility Tech Lead	Wei-Ying Chen
Irradiation Facility	None
PI	Philip Edmondson
PI Email	[email protected]
Project Type	RTE
RTE Number	1090