טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentGoldenberg Dov
SubjectSystem Aging of Explosives and Propellants - A Critical
Review
DepartmentDepartment of Quality Assurance and Reliability
Supervisor Dr. Abraham Rotem


Abstract

The subject of this review is the aging phenomenon of explosives and propellants and its influence on the systems they are assembled in. The review offers a concise presentation of the major explosives and propellants, as well as some systems in which they are assembled in. Next the phenomenon of aging and the methodology of aging surveillance programs are discussed. By definition, the aging phenomenon involves a slow degradation in the quality of materials and systems. The influence of aging on explosives and propellants, can manifests itself in two ways:

a)      A severe degradation of the performance and function, or physical deformations which result in lower reliability.

b)      A spontaneous and uncontrolled initiation, which presents a safety hazard.

In order to prevent reduced reliability or safety in long-term projects, it is necessary to assess and survey the effects of aging processes. The aging surveillance program includes two phases:

1.   Accelerated Testing- An approach utilizing severe stress conditions in order to accelerate the aging process. It is done by using a test environment that is more severe than the one experienced during normal equipment use.

2.    Real-time aging testing- In this approach the oldest parts or samples are tested. The main advantage of this approach is that the obtained results are completely analogous to the real aging process.

The aging surveillance program combines these two approaches: The first approach is used to estimate service life, while and the second approach is used for validation of the estimated service life.
The review presents several aging cases of explosives and propellants, as well as explosives and propellants systems. Although each case presents a particular behavior, an effort has been made to find similarities between the environment factors which influence the aging process.