To determine the Paris-Erdogan law parameters (K-threshold, C, and m) from the da/dN vs ΔK data, you need to perform a regression analysis of the logarithmic form of the Paris-Erdogan law, which is given by:

ln(da/dN) = ln(C) + m ln(ΔK)

Here are the steps to perform this regression analysis:

By following these steps, you should be able to determine the Paris-Erdogan law parameters (K-threshold, C, and m) from the da/dN vs ΔK data.

Dear Faisal Qayyum

May I request you to please share some references for the statement "The K-threshold is the value of ΔK at which da/dN = 1". I would also like to know about the factors used to convert test data in design data.

Regards

Naveen

My sincere thanks to Mr. Faisal Qayyum for your expert input, which helped me. I would also like to thank Mr. Filippo Piccini and Mr. Naveen Bhatt for taking out the time for my problem.

thanks regards

bhanu partap