Field Metallurgical Replication

FMR is a non destructive metallurgical inspection technique that is used forevaluating plant equipment such as heaters, boilers, piping and reactors. Bycomparison, cutting samples for laboratory testing is often more expensive,takes the equipment out of service and can be difficult to repair.

FMR is a simple process. Using portable equipment, the metal surface isground and polished to a mirror finish. The polished surface is subesquentlyetched to reveal the microstructure. A replica of the etched surface is thenmade with a thin piece of acetate film.

The replica can then be examined back in the field using a portable optical microscope or in the laboratory.This process gives our metallurgicalengineers the ability to examinemicrostructural features such as grainsize, cracks, carbides, creep and otherdamage mechanisms. It can confirmobservations made by other non-destructive methods such as acousticemission tests, penetrant examinationand ultrasonic flaw detection and takeit a step further to identify the nature ofthe flaw. For example, whether a crackis intergranular corrosion or transgran-ular fatigue can be determined.

Field Metallurgical Replication (FMR) is often the least disruptive and most cost-effective option for metallurgical examination when making important run,repair or replace decisions.

Polished FMR site on a boiler tube.

FMR showing cracked nozzle adjacent to weld and through base metal.

FMR should be considered if a component is in high temperatureservice or requires the use of a non destructive technique. One major advantage is that you don’t have to cut any samples for analysis and the equipment may not need to be taken out ofservice for this inspection.

When evaluating plant equipment, field metallurgical replicationcan be an important tool for making run, repair or replace typedecisions.

All questions of service life involve materials. SES has a perma-nent full-time staff of 16 metallurgists and materials engineers instrategically located offices throughout the United States (Houston,Texas, Cincinnati, Ohio, New Orleans & Baton Rouge, Louisiana),all devoted to diagnosing the materials suitability for continuedservice. SES can provide teams of metallurgists and technicians toconduct the in-situ FMR assessments or, if needed leverageresources back at one of our three laboratories.This approach enables usto quickly assess degrada-tion mechanisms thatimpact the service life ofyour equipment.

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Microstructure of carbon steel, showing ferriteand pearlite matrix on a field replica.

Replication site across a weld joining a large diameter tree and pipe.

In-situ surface preparation.