HCF Crack Propagation
Fatigue cracking typically occurs after thousands or millions of load cycles at stress levels below the component failure threshold. During cycling, the material develops microscopic flaws that expand into cracks. Once initiated, these cracks will grow until they are detected and repaired or they cause the part to fail.
This video illustrates a constant amplitude fatigue test using our MTS 810 Servo-hydraulic System. What begins as a microscopic crack – unseen to the naked eye – develops into a large fissure that propagates through the entire coupon.
Laser peening enhances material resistance to crack initiation and propagation, and can even be applied to arrest the growth of existing cracks.