https://nova.newcastle.edu.au/vital/access/ /manager/Index en-au 5 https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:41642 Wed 10 Aug 2022 08:43:25 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:32465 Wed 06 Jun 2018 14:04:16 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:39087 2AlB₂, using a combination of experimental characterization and first-principles calculations. We find that Fe₂,AlB₂ is more tolerant to radiation-induced amorphization than MoAlB, both at 150 ℃ and at 300 ℃. The results can be explained by the fact that the Mo Frenkel pair is unstable in MoAlB and as a result, irradiated MoAlB is expected to have a significant concentration of Mo_Al antisites, which are difficult to anneal even at 300 ℃. We find that the tolerance to radiation-induced amorphization of MAB phases is lower than in MAX phases, but it is comparable to that of SiC. However, MAB phases do not show radiation-induced cracking which is observed in MAX phases under the same irradiation conditions. This study suggests that MAB phases might be a promising class of materials for applications that involve radiation.]]> Tue 14 May 2024 09:12:30 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:41377 Tue 02 Aug 2022 15:34:28 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:26983 15 ions cm⁻². The evolution of microstructure and induced defects of the irradiated sample with different doses was surveyed by combining grazing incident X-ray diffraction (GIXRD) using synchrotron radiation and variable energy positron beam analysis (PBA). With increasing irradiation dose, the crystallinity degrades gradually and leads to a combination of damaged Ti₃SiC₂ in combination with the precipitation of a TiCₓ phase. For high dose irradiation, a nano-dispersed TiCₓ phase becomes the dominant component. The PBA measurements indicate the formation of a new large vacancy-type defect that could be a cluster or void. The combination of GIXRD and PBA demonstrates that the damage of the MAX phase is more serious in the first 10 nm surface layer than that in the deeper layers closer to the final resting position of the projectile in the solid. The possible damage mechanisms have been discussed.]]> Sat 24 Mar 2018 07:26:59 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:25135 Sat 24 Mar 2018 07:17:12 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:46799 Mon 29 Jan 2024 18:41:29 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:50465 Mon 29 Jan 2024 18:27:53 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:48689 Mon 27 Mar 2023 16:03:58 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:46106 2AlC MAX phase thin films prepared by radio-frequency magnetron sputtering were irradiated at room temperature by 100 keV helium ions to a fluence of 1 × 10¹⁷ ions cm⁻². The effects of thermal annealing on the structural and mechanical properties of the helium-irradiated Cr₂AlC films as well as the helium release were investigated by grazing-incidence X-ray diffraction (GIXRD), Raman spectroscopy, and scanning electron microscope (SEM) in combination with nano-indentation and elastic recoil detection (ERD) analysis. The irradiation-induced structural damage in the Cr₂AlC is significantly recovered by thermal annealing at temperatures around 600℃, attributed to high defect diffusivity. After annealing to 750℃, the hardness of irradiated films recovered almost completely, which is ascribes to both defect recombination and reformation of damaged chemical bonds. Substantial helium release occurring at this annealing temperature is closely related to the damage recovery due to helium irradiation.]]> Fri 11 Nov 2022 12:05:10 AEDT ]]>