Papers by Keyword: Time-to-Failure

Abstract: When assessing the reliability parameters, the traditional method is to deal with a large quantity of data obtained through test and to get the result with high confidence. But small sample size and the lack of test data of mechanical items make the traditional method have weakness. If the Bayesian method can be used properly, accurate assessment will be derived even if it is lack of data. What is discussed in this paper are: 1) determination of prior distribution, 2) reliability assessment based on pass/fail data with Beta distribution, Gamma distribution and cut-tail normal distribution as prior distribution, and 3) reliability assessment based on time-to-failure with Weibull distribution and normal distribution as prior distribution.

Abstract: This paper investigates failure behavior tests of T300/AG80 composite laminated specimens under tensile and compressive preload using a load holding device and laser irradiation from an Nd: YAG laser. By changing the magnitudes of the preload and the power densities of the laser, the effects of preload and laser power density on the time-to-failure of the specimens were observed. The response process of specimens was synchronized taken in using high-speed camera in experiment. The experimental results showed that tensile mechanical properties of T300/AG80 composite laminated specimens were obviously superior to ones in compression test. The relational expressions between the time-to-failure of specimens and pre-loads as well as with laser power densities were acquired through fitting experiment data. The time-to-failure reduced with the pre-load increasing, the relationship is approximating linear when the laser power density kept invariable. When the pre-load kept unchanged, the time-to-failure reduced as the laser power density increased. The relationship is approximating exponential. A basis for life prediction of structure mechanically loaded in either tension or compression during the irradiation by laser is provided by fitting expression.