(1)The acceleration factor is a unitless number that relates a product's life at an accelerated stress level to the life at the use stress level. It is defined by:
(1)
where:
Lu is the life at use stress level.
LA is the life at the accelerated level.
As it can be seen in Eqn. (1), the acceleration factor depends on the life-stress relationship (i.e. Arrhenius, Eyring, etc.) and is thus a function of stress.
The acceleration factor vs. stress plot is generated using Eqn. (1) at a constant use stress level and at a varying accelerated stress. In Figure 9, the acceleration factor vs. stress was plotted for a constant use level of 300K. Since LA = Lu, the value of the acceleration factor at 300K is equal to 1. The acceleration factor for a temperature of 450K is approximately 8. This means that the life at the use level of 300K is eight times higher than the life at 450K.
Fig. 9: Acceleration Factor vs. Stress Plot
See Also:
Plots
Go
to Weibull.com
Go to ReliaSoft.com
©1998-2010. ReliaSoft Corporation. ALL RIGHTS RESERVED.