class reliability.PoF.creep_failure_time(temp_low, temp_high, time_low, C=20, print_results=True)

This function uses the Larson-Miller relation to find the time to failure due to creep.

The method uses a known failure time (time_low) at a lower failure temperature (temp_low) to find the unknown failure time at the higher temperature (temp_high).

This relation requires the input temperatures in Fahrenheit. To convert Celsius to Fahrenheit use \(F = C × 1.8 + 32\)

Note that the conversion between Fahrenheit and Rankine used in this calculation is \(R = F+459.67\)

For more information see Wikipedia.

  • temp_low (float, int) – The temperature (in degrees Fahrenheit) where the time_low is known

  • temp_high (float, int) – The temperature (in degrees Fahrenheit) which time_high is unknown and will be found by this function

  • time_low (float, int) – The time to failure at temp_low

  • C (float, int, optional) – The creep constant. The default is 20. Typically 20-22 for metals.

  • print_results (bool, optional) – If print_results is True, the output will also be printed to the console.


time_high (float) – The time to failure at the higher temperature.