A chemical etchant for PuO2

JOURNAL

OF NUCLEAR

MATERIALS

19

(1966)

A CHEMICAL

215.

of

NORTH-HOLLAND

ETCHANT

VIRGINIA University

0

FOR

PUBLISHING

CO.,

AMSTERDAM

PuOs*

SHADDEN

California, Los Alamos Scientific

Laboratory, Los Alamos,

New

Mexico,

USA

Received 2 February 1966

A method

of

chemically

etching

PuOs

to

reveal grain boundaries and twins and which distinguishes between PuOs//?-PusOa in a sintered compact has been developed. The specimen shown in fig. 1 was ground through 600 grit paper and lapped with 14.5 ,um A1203 and Linde A in CC14 on vibratory polishers. It was etched with a solution consisting of equal volume proportions of concentrated HP and HNOs. A drop of the etchant was placed on the polished surface to form a meniscus which was then heated. To accomplish the heating, the specimen was first placed about an inch from a 250-W infrared lamp until the etchant started to vaporize (approximately 15 set) and was then moved to a position about 3” from the lamp for an additional 50 sec. The specimen was then allowed to cool for 30 set with the meniscus intact before being rinsed with CC14. (The cooling step is necessary before rinsing because otherwise a layer would form which would obscure the structural detail). *

Rinsing was followed by ultrasonic cleaning in CC4 to remove all traces of the etchant before the structure

was viewed and photographed.

Fig. 1. Chemically etched PuOz sintered compact. 500 x

Work performed under the auspices of the U.S. Atomic Energy Commission.

215