Visibility of corrosion cracking properties by replication method.

Replica testing is metallography analysis which has potential to become high demand in oil and gas industry. It is considered critical for assessing the integrity health of the equipment, which operates under various plant conditions. Replication methods can be beneficial in microstructure assessments for monitoring in-service degradation of critical components of oil and gas industry. The purpose of this research is to apply replication method to evaluate the properties of microstructure, identifying intergranular/transgranular crack propagation and identifying the best etching time. The replication method was successfully conducted on the pipe elbow and the replica sample was obtained. Then the replica sample was observed under optical microscopy. In microstructure analysis, there is a crack propagated intergranularly along the weld joint and it was confirmed that there is presence of crack along circumferential weld joint between pipe and elbow. The etching process is accomplished by applying Nital solution to the specimen surface are for 5 seconds to 15 seconds. The results obtained in the microstructure assessment show that the replication method can be exceptionally efficient in industry. To be concluded, replica can be needed as NDT technique to identify microstructure and crack propagation on 'live' assets. [ABSTRACT FROM AUTHOR]