Hostname: page-component-78c5997874-dh8gc Total loading time: 0 Render date: 2024-11-02T23:48:14.092Z Has data issue: false hasContentIssue false
  • English
  • Français

Annealing of Alpha-Recoil Damage in Natural Titanite, CaTiSiO5.

Published online by Cambridge University Press:  21 February 2011

Ray K. Eby  and
Rodney C. Ewing
Ray K. Eby
Affiliation:
Department of Geology, University of New Mexico, Albuquerque, New Mexico 87131.
Rodney C. Ewing
Affiliation:
Department of Geology, University of New Mexico, Albuquerque, New Mexico 87131.
Get access

Abstract

Isothermal and isochronal annealing of alpha-recoil damage was performed on the mineral titanite, CaTiSiO5. Crushed-grain samples were heated for 21 hrs, at 100°C intervals from 300°-700°C. HRTEM imaging of alpha-recoil collision cascades (amorphized regions), after each temperature interval, showed that there was no change in the abundance or appearance of the cascades at 300°C, but an apparent decrease in cascade size occurs at 400°C (from 3.8 nm to 2.4 nm diameter). A decrease in the size of collision cascades may indicate repair of interstitial defects at cascade boundaries (where interstitials dominate), while the cascade cores remain amorphous (cores acquire more extensive knock-on damage). At 500°C, the number of collision cascades observed decreases by greater than 90%, indicating major annealing of the amorphous cascade cores, and precipitates appear on titanite grain surfaces. At 600°C, changes do not occur. At 700°C, both the cascades and precipitates are absent; the alpha-recoil damage is fully annealed.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 183: Symposium E – High Resolution Electron Microscopy of Defects in Materials , 1990 , 297
Copyright
Copyright © Materials Research Society 1990

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Refrences

1. Hayward, P.J., in Radioactive Wasteforms for the Future, edited by Lutze, W.L. and Ewing, R.C. (Elsevier Scientific Publishers, New York, 1988), p. 778.Google Scholar
2. Vance, E.R., and Metson, J.B., Phys. Chem. Min. 12, 255 (1985).10.1007/BF00310337Google Scholar
3. Hawthorne, F.C., et al., Amer. Miner. (submitted 1990).Google Scholar
4. Lumpkin, G.R., Ewing, R.C., Eby, R.K. (in preparation 1990).Google Scholar
5. Hogarth, D.D., Moyd, R., Rose, R.E., Steacy, H.R., in Field Excursion A47-C47, edited by Glass, D.J., (Int. Geol. Congr. Publication, 24th session, 1972), p. 79.Google Scholar