This title appears in the Scientific Report :
2006
Please use the identifier:
http://dx.doi.org/10.1016/j.actamat.2005.11.030 in citations.
Microstructure of helium-implanted alpha-Al2O3 after annealing
Microstructure of helium-implanted alpha-Al2O3 after annealing
Polycrystalline alumina (alpha-Al2O3) was homogeneously implanted to depths of 80 pm with helium to a concentration of 1000 appm at room temperature, and subsequently annealed at temperatures from 800 to 1400 degrees C for 0. 1-10 h. The microstructure was investigated using transmission electron mi...
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Personal Name(s): | Chen, J. |
---|---|
He, Z. Y. / Jung, P. | |
Contributing Institute: |
Streumethoden; IFF-ISM |
Published in: | Acta materialia, 54 (2006) S. 1607 - 1614 |
Imprint: |
Amsterdam [u.a.]
Elsevier Science
2006
|
Physical Description: |
1607 - 1614 |
DOI: |
10.1016/j.actamat.2005.11.030 |
Document Type: |
Journal Article |
Research Program: |
Großgeräte für die Forschung mit Photonen, Neutronen und Ionen (PNI) Kondensierte Materie |
Series Title: |
Acta Materialia
54 |
Subject (ZB): | |
Publikationsportal JuSER |
Polycrystalline alumina (alpha-Al2O3) was homogeneously implanted to depths of 80 pm with helium to a concentration of 1000 appm at room temperature, and subsequently annealed at temperatures from 800 to 1400 degrees C for 0. 1-10 h. The microstructure was investigated using transmission electron microscopy. Dense populations of faulted dislocation loops and of bubbles were observed from 1000 to 1200 degrees C. Most loops had habit planes of I 10 10 1 and some of (0 0 0 1), and both were identified to be of interstitial type. The loops on (0 0 0 1) had a round shape while those on I 10 10 1 were rectangular with the short edges in [0 0 0 1]. On annealing at 1400 degrees C, the dislocation density decreased dramatically. Bubbles became visible at T >= 1000 degrees C (I h). They were associated with loops and were arranged in disc-shaped arrays. Disc-shaped features of vacancy type (platelets) were observed in a narrow window of annealing temperatures and times around 1200 degrees C and 0. 1 h. Bubbles were observed on low-angle grain boundaries but not on normal grain boundaries. Platelets were been observed in magnesia (MgO), implanted from 1000 to 2400 appm with subsequent annealing for I It at temperatures from 800 to 1000 degrees C. The temperature regime where helium clustering occurs is in accord with that of previously observed lattice expansion in both materials. (c) 2006 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. |