When metal fails: The role of metallurgy in claims investigations

When an engine component breaks, a wire rope snaps or a tube begins to leak, insurers, vessel owners, operators and other stakeholders need answers fast. 

What caused the failure? How did it develop? And does the damage point to a larger concern?

Those details can significantly influence how a claim is evaluated and resolved. In these situations, metallurgical investigations can provide the technical evidence needed to distinguish between competing causes and make more informed claim decisions. 

Tracing the path to failure

Metallurgy is the study of metals, their properties and how they change through manufacturing, use and exposure to different environments. In a failure investigation, the metallurgist works backward from the damage to reconstruct the events that led to the loss.

That process may begin with an on-site or onboard inspection, nondestructive testing and sample collection. Laboratory examinations can then provide a closer look at a material’s composition, mechanical properties, microstructure and fracture surface. Depending on the circumstances, the investigation gathers the necessary evidence for expert reporting, mediation or arbitration proceedings. 

The goal isn’t simply to identify a damaged component. It’s to understand the factors that contributed to the failure and establish whether operational conditions, maintenance practices, environmental exposure or a latent defect played a role. 

The clues hidden inside damaged metal

Before metallurgists can determine what contributed to a failure, they need to understand how the material itself deteriorated or fractured. Certain corrosion and cracking patterns can provide important clues about the conditions a component experienced, how damage developed and where the investigation should focus next.

Common types of corrosion

Corrosion isn’t always uniform or easy to detect. Different patterns can point to different environmental conditions:

• Pitting corrosion: Small, localized cavities that can penetrate deep into a metal surface while remaining difficult to detect

• Crevice corrosion: Material deterioration that develops in tight gaps or confined spaces where environmental conditions accelerate metal loss locally
• Tubercles: Corrosion deposits that form on a surface and may conceal more extensive damage underneath

Common types of cracking

Cracks can also provide valuable insight into the progression of a failure. The appearance and location of a crack enable metallurgists to distinguish between different contributing factors:

• Stress corrosion cracking: Cracks caused by the combined effects of mechanical stress and a corrosive environment
• Fatigue cracking: Progressive damage resulting from repeated loading and unloading cycles
• Intergranular cracking: Cracking that follows the grain boundaries within a metal and may indicate material or environmental issues

Turning observations into evidence

Visual observations are only the starting point. Determining the cause of a failure often requires a combination of laboratory techniques, each designed to reveal different pieces of the story:

• Chemical composition analysis: Verifies metal grades and identifies unexpected elements or contaminants
• Optical microscopy: Examines a material’s microstructure, identifies crack paths and evaluates manufacturing or heat-treatment conditions
• Scanning electron microscopy (SEM-EDS): Produces high-magnification images of fracture surfaces and corrosion product layers, and provides elemental analysis
• Mechanical testing: Evaluates tensile, hardness, impact and fracture toughness to see whether a material meets expected performance requirements
• Corrosion testing: Assesses how a material performs under specific corrosive conditions or environments

The claim questions that matter most

While each investigation is different, the questions stakeholders need to answer are often the same.

1. Was the failure caused by a defect or by operating conditions?

Understanding where a failure originated can help evaluate potential contributing factors, identify responsible parties and determine the most appropriate path for the claim.

In one engine investigation, cracks discovered on the external surface of a piston crown were ultimately traced to an internal feature that was not apparent from the visible damage alone. In another case, a failed connecting rod and bolt assembly revealed evidence of how the fracture developed over time. Insights like these can help stakeholders better understand what contributed to a loss and make more informed decisions as the claim moves forward.

2. Did the equipment fail gradually or suddenly?

The timing and progression of a failure can provide important context when evaluating a loss. A gradual deterioration may raise different questions than a failure that occurs during a single event, particularly when stakeholders are assessing maintenance history, liability and the circumstances surrounding the incident.

Investigations involving cargo-crane and offshore-crane wire ropes demonstrate how metallurgical analysis can help answer these questions. By examining individual wire fractures and the condition of the rope, metallurgists can gather evidence about how the failure developed and better understand the events leading up to the loss.

3. Is the failure isolated or part of a larger problem?

When critical equipment fails, stakeholders need to understand whether they’re dealing with a single damaged component or a condition that could affect a broader system. The answer can influence repair planning, operational decisions and the overall scope of a loss.

Process equipment investigations often help provide that perspective. In cases involving heat exchanger tubes, reheater tubes and boiler tubes, metallurgists examine patterns across the system rather than focusing solely on the failed component. The location of leaks and evidence found within the materials can provide valuable insight into how conditions evolved over time and whether additional areas warrant closer examination.

From damaged component to defensible conclusion

When the cause of a failure isn’t immediately clear, the answers are often hidden within the metal itself. By examining material characteristics, fracture morphology and signs of degradation, metallurgists can uncover the factors that contributed to a loss and provide stakeholders with a clear understanding of what happened. 

Whether the loss involves a vessel, industrial equipment or critical infrastructure, Sedgwick’s metallurgical specialists help clients move from uncertainty to evidence-based conclusions. By combining technical expertise with hands-on investigative experience, they provide the insights needed to evaluate potential exposures and move complex losses toward resolution. Learn more about our global specialty offerings.