Is it possible that the correlations between structural disordering and amorphization resistance are different for pyrochlores under different irradiations? As demonstrated by numerous studies, pyrochlores with higher disordering degree are generally more resistant to ion irradiation induced amorphization. I wonder that is it possible or reasonable that, under some ion irradiations, pyrochlores with higher disordering degree are less amorphization resistant? And why?
Thank everyone!
This is a very good question! There may be some variation in the correlation depending upon the nature of the radiation. Using ions, you could think about the possible effects of different ion mass and energy and, to a first approximation, how the energy is partitioned to nuclear versus electronic stopping processes. For any given pyrochlore composition, of which many are possible, it also relates to the energetics of defect formation and migration which can also be approached using atomistic simulations. Rod Ewing and Bill Weber (and their students and post docs) have done some nice work in this area, but there is still room to explore the problem more deeply, in my opinion. In some cases the disordering may be strongly influenced by the composition, e.g., my colleagues (Ashbrook, De los Reyes, Z. Zhang, and others) have shown that Sn has a strong drive to remain in 6 fold coordination through the pyrochlore-defect fluorite phase transformation. It's an interesting problem, for sure.
Hi Dongyan, I think the structure disordering you mentioned should be topological disordering, because amorphous structure is an structural disordering also. I feel the issue you raised is similar with a issue in solid mechanics, namely, how the crack tip response to the external loading. there are three possibilities, the first is bond cleavage at the crack tip, the second is the dislocation emission from the crack, the third is the amorphization around the crack tip. right now, i dont known how to tell which one will be preferred to happen. I hope i could find some hints from the replies by the experts to your poster.
- Badges
- Science topic
- Similar topics
- Physical Sciences
- Materials Science