Supporting Utilities for QALT Planning and Analysis
Time-Dependent Stress Profiles
The cumulative damage life-stress model (available only in ALTA PRO) can handle data from tests where the stress varies with time (e.g., a step-stress or ramp-stress profile). You can define and store any number of stress profiles, then easily assign the appropriate profile to each point in an ALTA data sheet.
Each segment in a profile can be associated with a specific stress value (e.g., temperature is 310 K from 0 to 100 hours and 320 K from 101 to 200 hours) or a time-dependent function (e.g., start from a temperature of 310 K and then gradually increase by 10 K with each hour of testing).
Now in Version 10, we've added a new Stress Profile Plot for each cumulative damage analysis that shows both the profile and the failures that occurred in each segment!
Accelerated Life Test Planning
The ALTA Test Plan utility implements the complex mathematical models required to design an effective accelerated life test plan. The tool offers a choice of one-stress or two-stress test planning methods. Based on your inputs about the expected failure behavior and available test time, the software recommends the stress levels to be tested and the most effective allocation of available test units to each level.