Reading the Fingerprints Left by Broken Materials

Every material failure leaves behind physical evidence, much like a fingerprint at a crime scene. Whether it's a broken valve, a ruptured pipeline, or a medical implant malfunction, the clues we find can definitively reveal what went wrong and allow us to confirm why it happened.

At EDT, our materials evaluation and testing services are forensic investigators for your most challenging cases. But what exactly does this look like in practice, and why does it matter for legal and insurance professionals?

Materials Evaluation and Testing: Revealing Hidden Causes of Failures

When materials fail—metal, plastic, glass, or otherwise—they don’t just break arbitrarily. They fracture in characteristic ways depending on the cause. For instance:

• Fatigue failures occur from repetitive stress, like bending a paperclip back and forth until it snaps.
• Overload failures happen suddenly and violently, similar to tearing a tab off a soda can in one quick motion.
• Corrosion or degradation leaves distinct patterns that pinpoint long-term deterioration.

By examining these fracture-specific features through specialized laboratory analytical techniques—such as optical microscopy, scanning electron microscopy, and metallography, we can accurately determine the root cause of the failure.

When Visual Evidence Isn't Enough

Visual inspections alone can sometimes lead you astray. Take a train suspension coil fracture that I investigated. Visually, it initially appeared to have failed due to fatigue—a repetitive stress issue indicated by a specific crack pattern. But microscopic examination revealed fractographic features that confirmed the cause of the failure was embrittlement from localized overheating during manufacturing, not fatigue. 

That subtle difference dramatically altered the direction of the investigation and helped the client understand what was needed to assess the remaining fleet and prevent further failures.

Common Misunderstandings about Material Failures

One widespread misconception is that materials fail unpredictably or that visual checks suffice to determine causes. Even experienced engineers sometimes overlook critical details in a material’s behavior under different conditions.

For example, an improperly designed propeller blade for a cargo ship sustained fatigue cracking soon after installation because sharp corners created stress points. If the designer had fully understood how the material would perform under real-world conditions, that expensive failure could have been avoided.

Best Practices for Preserving Evidence

To ensure accurate analysis and legal defensibility, follow these guidelines when faced with a potential material failure:

• Don’t clean or alter the failed component. Attempts to clean rust or corrosion can unintentionally destroy microscopic clues vital for analysis.
• Don’t attempt to put the two halves of a fractured component together. I know this is tempting, but it will alter/damage the fracture surface.
• Preserve original design and installation records. Background information such as material specifications, purchase records, and installation dates significantly aids in our investigation.
• Contact an expert immediately. The earlier we can access and secure the evidence, the better your outcomes will be.

When Material Testing Makes All the Difference

For legal and insurance professionals, definitive answers are crucial. Material testing doesn't just offer insights; it provides irrefutable proof of why a component failed. Unlike some disciplines where expert opinions can conflict, materials analysis is grounded in tangible evidence that cannot be easily disputed.

Ultimately, understanding the "fingerprints" left behind by material failures equips you with the clarity you need, whether preparing for court, negotiating settlements, or simply seeking the truth behind complex cases.

When it comes to material failures, the evidence speaks loud and clear. At EDT, we’re here to ensure you hear every word.

About the Author

Scott Lieberman, Ph.D., P.E., CWI, LEED AP, is the Director of Metallurgical and Materials Engineering at Engineering Design & Testing Corp. (EDT). Licensed as a Professional Engineer in New York, New Jersey, Connecticut, California, Michigan, and Minnesota, Scott specializes in forensic investigation and failure analysis of metallic and non-metallic materials across diverse industries, including construction, automotive, marine, aerospace, medical devices, energy, fire protection, petrochemical, and electronics.