Accession Number:

ADD002402

Title:

Activated Aluminum Tracer Tag.

Descriptive Note:

Patent,

Corporate Author:

DEPARTMENT OF THE NAVY WASHINGTON D C

Personal Author(s):

• Murray,Kenneth M.

Report Date:

1975-12-02

Pagination or Media Count:

4.0

Abstract:

The patent concerns a method of treating a piece of aluminum and detecting the presence of the treated aluminum in an assembly without disassembly of the parts. The small piece of aluminum is made radioactive by irradiation with x-rays of at least 23 MeV to produce the reaction 27Algamma, alpha n22Na. The presence of the aluminum part is determined by isotope decay which emits a positron. The positron subsequently annihilates emitting two 180 degree correlated 0.511006 MeV gamma rays. These gamma rays are detected in coincidence by use of a pair of detectors and associated coincidence and counting electronics. Part of a primer of a naval shell contains an aluminum shear pin which is to be detected. A counting system is used to detect positrons from the 22Na activity in the shear pin.

Descriptors:

• *Aluminum
• *Tracer studies
• *Detection
• *Patents
• Irradiation
• Electromagnetic radiation
• Naval guns
• Ammunition
• Pins

Subject Categories:

• Metallurgy and Metallography
• Radioactivity, Radioactive Wastes and Fission Products
• Ammunition and Explosives

Distribution Statement:

APPROVED FOR PUBLIC RELEASE