Larson-Miller parameter:
For material of example of calculate life in hours at temperature of 900oC, and at σ = 20 MPa.
Solution
Larson-Miller parameter is given by
m = T (ln t + 85.75)
Use T = 900 + 273 = 1173 K
But m = 16.75 × 10^{4}
From Example 1.7 at σ = 20 MPa
∴ 1173 (ln t + 85.75) = 16.75 × 10^{4}
∴ ln t =(16.75 × 10^{4 }/1173 )- 85.75
= 142.8 - 85.75 = 57.05
∴ t = 5.95 × 10^{24} hours