Rashiga Walallawita

W = 25*10^(-3)m

a = 6*10^(-3)m

B = 5*10^(-3)m

Take a geometric correction factor Y = 1.12 (this is commonly used)

K (stress intensity factor) = (P*Y)/(B*sqrt(W))

P = K*B*sqrt(W)/Y (this will be your required force for pre-crack initiation)

Hello Ashrith Kumar Shetty

Thank you for your reply!

I will try it out and get back to you.