Anomalies in Long-Crack Propagation at Low ΔK in Some Engineering Alloys
2024

Unusual Crack Growth Behavior in Engineering Alloys

publication Evidence: moderate

Author Information

Author(s): Kujawski Daniel, Vasudevan Asuri K.

Primary Institution: Western Michigan University

Hypothesis

What causes the unexpected behavior of long cracks in certain alloys at low stress intensity factor ranges?

Conclusion

Some engineering alloys exhibit unexpected acceleration in fatigue crack growth rates at low stress intensity factors, challenging traditional fracture mechanics assumptions.

Supporting Evidence

  • Unusual fatigue crack growth behavior was first reported in the IMI 834 alloy.
  • Some alloys do not show a consistent decrease in crack growth rate with decreasing stress intensity.
  • The Marci effect indicates that long cracks can grow at low stress intensity factors, challenging traditional design assumptions.

Takeaway

Some materials can grow cracks faster than expected when they are under low stress, which can be dangerous for structures like bridges and airplanes.

Methodology

The study involved analyzing fatigue crack growth behavior in various alloys under controlled stress intensity conditions.

Limitations

The mechanisms behind the observed anomalies are not fully understood and may not be applicable to all materials.

Digital Object Identifier (DOI)

10.3390/ma17246093

Want to read the original?

Access the complete publication on the publisher's website

View Original Publication