1992 Volume 10 Issue 2 Pages 302-308
In this paper, closure measurement of short fatigue crack by surface wave technique of ultrasonic testing is recommended. Surface wave could be good for measuring a closure of short crack, because surface wave has it's 75% energy within the region of 40% of it's wave-length from a surface.
To detect a short fatigue crack and to measure the closure of short crack, both the surface wave method and the strain compliance method was used.
Crack initiation was detected earlier by the surface wave method than the strain compliance method. The relation between crack growth rate da/dN and effective stress intensity factor range ΔAeff, obtained from the surface wave method showed a good agreement with those obtained from the strain compliance method.
