Nano-scale microstructure damage by neutron irradiations in a novel Boron-11 enriched TiB2 ultra-high temperature ceramic
Journal Article
·
· Acta Materialia
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Missouri Univ. of Science and Technology, Rolla, MO (United States)
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)
Ultra-high temperature transition-metal ceramics are potential candidates for fusion reactor structural and plasma-facing components. We reveal the irradiation damage microstructural phenomena in Boron-11 enriched titanium diboride (TiB2) using mixed-spectrum neutron irradiations, combined with state-of-art characterization using transmission electron microscopy (TEM) and high resolution TEM. Irradiations were performed using High Flux Isotope Reactor at ~220 and 620 °C up to 2.4 x 1025 n.m-2 (E > 0.1 MeV). The calculated dose including contribution from residual Boron-10 (10B) transmutation recoils, was ~4.2 displacements per atom. TiB2 is susceptible to irradiation damage in terms of dislocation loop formation, cavities and anisotropic swelling induced micro-cracking. At both 220 and 620 °C, TEM revealed dislocation loops on basal and prism planes, with nearly two orders of magnitude higher number density of prism-plane loops. HRTEM, electron diffraction and relrod imaging revealed additional defects on {10$$ \overline{1}\ $$0} planes, identified as faulted prism-plane dislocation loops. High defect cluster density on prism planes will induce a-lattice parameter swelling of TiB2, as reported in literature. This anisotropic lattice parameter swelling induced grain boundary micro-cracking, the extent of which decreased with increasing irradiation temperature. The dominance of irradiation defect clusters on prism planes is different than typical hexagonal ceramics where dislocation loops predominantly form on basal planes, causing c-lattice parameter swelling. Helium generation and temperature rise from the transmutation of residual 10B resulted in matrix and grain boundary cavities for the irradiation at 620 °C. In conclusion, the study additionally signifies isotopic enrichment as a viable approach to produce transition-metal diborides for potential nuclear structural applications.
- Research Organization:
- Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- Grant/Contract Number:
- AC05-00OR22725
- OSTI ID:
- 1484130
- Alternate ID(s):
- OSTI ID: 1636989
- Journal Information:
- Acta Materialia, Journal Name: Acta Materialia Journal Issue: C Vol. 165; ISSN 1359-6454
- Publisher:
- ElsevierCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Selection, processing, properties and applications of ultra-high temperature ceramic matrix composites, UHTCMCs – a review
|
journal | September 2019 |
Similar Records
Neutron irradiation-induced microstructure damage in ultra-high temperature ceramic TiC
Response of 11B enriched ZrB2 ultra-high temperature ceramic to neutron irradiation at elevated temperatures
In situ transmission electron microscopy of electron-beam induced damage process in nuclear grade graphite
Journal Article
·
Thu Dec 12 19:00:00 EST 2019
· Acta Materialia
·
OSTI ID:1649527
Response of 11B enriched ZrB2 ultra-high temperature ceramic to neutron irradiation at elevated temperatures
Journal Article
·
Thu Jun 13 20:00:00 EDT 2024
· Acta Materialia
·
OSTI ID:2376345
In situ transmission electron microscopy of electron-beam induced damage process in nuclear grade graphite
Journal Article
·
Sun May 01 00:00:00 EDT 2011
· Journal of Nuclear Materials
·
OSTI ID:1022745