Aging and Surveillance Program Minuteman II/III Stage II Program Progress.
Abstract
Statistically significant correlations, relationships and trends have been developed throughout the aging program which can be applied to service life assessment. Measurement of moisture within sealed rocket motors indicates that moisture equilibrium in the bore is reached in approx. 2 years. Average moisture following equilibrium was approx. 15% RH measured at 80 F (or 21% RH measured at 70 F). A total of 13 full-scale motors which were weather sealed at time of manufacture have been measured for moisture content. Motors ranged in age from 3.6 to 77..6 months at time of test. Testing of plug samples removed from 3 motors indicates considerable variation in propellant and properties within given motor due to propellant batch-to-batch variation. With aging, propellant properties indicate continued hardening to 36 months. Bond properties are generally unchanged in the chamber area with aging, but variation among motors tends to be large. Bond strength in the aft ends of all motors is decreased with age, expected based on testing of approx. 130 excise samples. Gradients in mechanical and chemical properties were measured as a function of distance from the bondline interface. For plug samples removed from Motors MSEX-2 and R7-032, data indicate higher modulus and crosslink density (and correspondingly lower strain capability) adjacent to the bondline (0.1 in.) than at distances greater than 1. in. Propellant strength is not affected by proximity to the bondline.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1987
- Accession Number
- ADA181254
Entities
Organizations
- Aerojet Rocketdyne Holdings