Materials Failure Analysis — Fracture, Contamination & Polymers
A useful failure investigation explains the evidence behind a mechanism and its limitations, not simply the instruments used. Start with the component's service history and preserve the failed surfaces before selecting microscopy, chemical analysis or mechanical tests.
Frame competing hypotheses before cutting
Document where and when the failure occurred, loading, environment, process history and prior repairs. Distinguish fracture initiation from damage caused after final separation. Non-destructive inspection and macroscopic photography can establish orientation and sampling priorities before sectioning removes evidence. Include unaffected comparisons where available, but avoid treating a different production lot as a perfect control without recording its differences.
Use methods to answer specific questions
Fractography examines fracture features; metallography examines microstructure; SEM/EDS helps describe morphology and local elemental composition. Polymer investigations may require FTIR and thermal analysis, while coating problems involve substrate preparation and interface behaviour. No single spectrum or image identifies root cause automatically. Agree which observations support each hypothesis and when additional tests would discriminate unresolved alternatives.
Separate causation and corrective-action evidence
The report should distinguish measured results, interpretations, uncertainty and missing context. A proposed corrective action may need a separate verification experiment or service simulation. For disputes, agree chain of custody, destructive permissions, retained evidence and witness arrangements in advance. Choose a provider with relevant failure-system experience and ask for method-specific scope rather than inferring capability from an industry directory label.
Sample considerations
- Send event chronology, drawings, process/heat-treatment records, loading and environmental history.
- Preserve fracture faces and contaminants; obtain handling instructions before cleaning, fitting fragments or cutting.
- Identify unaffected comparators, retention needs, confidentiality and destructive permissions.
Questions to ask a laboratory
- What evidence will distinguish initiation from secondary damage?
- Which tests resolve the competing mechanisms and which preserve evidence?
- Will the report separate confirmed observations, interpretations and unresolved limits?
Laboratories with relevant capabilities
- Metallurgical Technologies (Mooresville, NC) — Forensic root cause analysis
- Anderson Materials Evaluation (Columbia, MD) — Profile summary mentions “root cause”
- Exponent (Menlo Park, CA) — Profile summary mentions “root cause”
Frequently asked questions
- What should I send with a failed part?
- The failed part as found, an unfailed comparison part if available, drawings and material specification, and a written history of service conditions and events before failure.
- Should I clean the part first?
- No. Deposits, corrosion products and surface features on the fracture are evidence. Cleaning can destroy the information needed to identify the mechanism.
Sources and scope references
Related testing briefs
Confirm standard edition, jurisdiction and actual laboratory scope. Service references are not partnerships or endorsements.