Proof-testing and probabilistic lifetime estimation of glass fibers for sensor applications.
The mechanical reliability of sensing glass fiber is one of the important problems in the practical use of fiber-optic sensors. To ensure long-term reliability on a mass-production level, a method of proof-testing is applied to a sensing glass fiber that will be subjected to mechanical deformation in its service situation. We propose to employ a higher strain level (screening level) in the proof-testing with a fiber-recoating technique that can suppress excessive damage during the testing. We consider a standard lifetime of 15 years of automotive applications and ensure a practical level of failure probability by a model calculation by using the strength data of a prototype fiber with the method of fracture-mechanics theory.
Komachiya
M
M
Hitachi Research Laboratory, 1-1 Omika-cho 7-chome, Hitachi-shi , Ibaraki-ken319-1292, Japan.
Minamitani
R
R
Fumino
T
T
Sakaguchi
T
T
Watanabe
S
S