Creep calculations - application of Norton's power law
In this video I show you how to apply the Norton equation for calculating the n and Q parameters. These are typical exam questions, so it is good to know them.
Steps:
Rearrange the creep equation so you will be able to plot and fit linear equations.
Calculate all the data which can be calculated for the rearranged equation. For example: log(sigma), log(de/dt), 1000/T(in Kelvin), etc.
Get n by plotting log(sigma) vs log(de/dt). The slope of the fitting gives n.
Rearrange the equation, so you will get a linear-type of equation.
Using the freshly obtained n, calculate log(de/dt)-n*log(sigma). This will be on the Y-axis. The X-axis will be 1000/T, where T is given in Kelvin. Plot it.
Fit a linear on your plotted data. The slope (m) is the "-Q/(2303*R)" in the equation. Rearrange and express Q.
Done!
