THE NATURE OF RADIATION-INDUCED POINT DEFECT CLUSTERS

Journal Article · Thu Dec 01 04:00:00 EST 1960 · Phil. Mag.

DOI:https://doi.org/10.1080/14786436008238337· OSTI ID:4100138

Barnes, R S; Mazey, D J

The electron microscope was used to examine point defect clusters produced in copper and aluminum foils bombarded with 1.4 x 10/sup 17/ alpha - particles cm-/sup 2/. The foils were bombarded as a stack; and, in copper, both foils through which the alpha -particles had passed and that in which they came to rest appeared similar, containing dislocation loops (r approximately 200 A) and a background of more numerous and smaller dots (r approximately 20 A). The behavior at grain boundaries suggested that these two types of cluster were caused by different point defects. Whereas the dislocation loops normally annealed out at about 350 deg C, in the foil in which the alpha -particles came to rest (containing approximately 10/sup 15/ atoms of helium cm-/sup 2/) they grew to form a dislocation tangle, and eventually small helium bubbles (r approximately 40 A) appeared in the same number as the original small dots. The results indicate that the dislocation loops are caused by the clustering of irterstitial atoms and the small dots are clusters formed from vacancies. It is inferred that the helium atoms are in interstitial positions during the bombardment and form bubbles by nucleating upon the clusters. (auth)

• Research Organization: Atomic Energy Research Establishment, Harwell, Berks, Eng.
• NSA Number: NSA-15-007863
• OSTI ID: 4100138
• Report Number(s): AERE-R-3348
• Journal Information: Phil. Mag., Journal Name: Phil. Mag. Vol. Vol: (8) 5
• Country of Publication: United Kingdom
• Language: English

Related Subjects

ALPHA BEAMS
ALUMINUM
ANNEALING
ATOMS
BUBBLES
COPPER
CRYSTALS
DEFECTS
ELECTRON MICROSCOPY
FOILS
GRAIN BOUNDARIES
HELIUM
IRRADIATION
LATTICES
METALS, CERAMICS, AND OTHER MATERIALS
PRODUCTION
RADIATION EFFECTS