Dynamic Fatigue of Ultralow-Expansion Glass for Space Mirrors. Reissue A

reportActive / Technical Report | Accession Number: ADA205401 | Open PDF

Abstract:

Ultralow-expansion ULE glass is one of the primary materials used for space mirrors because its SiO2-TiO2 composition has a very low coefficient of thermal expansion. Several problems with cracking of this material in the Defense Satellite Program DSP led to the conclusion that insufficient design information was available to ensure reliability of the mirror structure. Accordingly, the Materials Sciences Laboratory of the The Aerospace Corporation undertook an investigation into the fracture behavior of ULE glass for space mirrors. Dynamic fatigue experiments were performed on two sets of samples optically polished and lightly ground to characterize the fracture behavior of this material in a humid environment. As expected, the flaw size distribution affects the expected lifetime at a given stress and failure probability. In addition, it is shown that the polished material is apparently less sensitive to subcritical crack growth than the unpolished glass.

Author(s):
Speece, Dana J.
Author Organization(s):
AEROSPACE CORP EL SEGUNDO CA MATERIALSSCIENCES LAB
Descriptive Note:
Technical rept.
Supplementary Note:
Supersedes report dated 8 Aug 1986, ADA172086.
Pagination:
0031

Security Markings

DOCUMENT & CONTEXTUAL SUMMARY

Distribution:
Approved For Public Release
Distribution Statement:
Approved For Public Release; Distribution Is Unlimited.

RECORD

Collection: TR
Identifying Numbers
Report Number(s):
TR-0086(6409-11)-1, SD-TR-86-49
Contract/Grant Number(s):
F04701-85-C-0086
Monitor Series:
TR-86-49, SD
 Subject Terms
Joint Capability Areas:
JCA_1.2.5_Lessons Learned; JCA_1.2.7_Experimentation; JCA_5_Command and Control
Modernization Areas:
Microelectronics; Space; Directed Energy
Communities of Interest:
Space
Descriptor(s):
*MIRRORS, *GLASS, *THERMAL EXPANSION, DEFENSE SYSTEMS, SIZES(DIMENSIONS), DISTRIBUTION, FRACTURE(MECHANICS), RELIABILITY, DEFECTS(MATERIALS), SUBCRITICAL ASSEMBLIES, HIGH HUMIDITY, MATERIALS LABORATORIES, TITANIUM DIOXIDE, FAILURE(MECHANICS), FATIGUE(MECHANICS), SAMPLING, ARTIFICIAL SATELLITES, COEFFICIENTS, CRACK PROPAGATION, CERAMIC MATERIALS, DYNAMICS, SILICON DIOXIDE, CRACKS, PROBABILITY
Field(s)/Group(s):
Ceramics, Refractories and Glass, Optics
Keyword(s):
CERAMICS, FATIGUE, ULTRALOW EXPANSION GLASS
Report Date:
1988 Oct 30