METALLOGRAPHIC REPLICAS

Replication is a nondestructive method that records and preserves the topography of a metallographic specimen as a negative relief on a plastic film or cellulose acetate. Surface preparation may be accomplished using manual,
mechanical, or electrolytic polishing methods. Following which the wetted plastic film is applied to the prepared surface with a suitable solvent, such as acetone or methyl acetate. After the film has dried, the replica is removed and permanently mount on a rigid slide to facilitate its microscopic analysis and to protect it from damage during subsequent transport and storage. Replication method is used in several case because of the advantages it provides. In fact it allows to get information about the residual life estimation of steel components and structures without compromising or affecting their usefulness.

One of the most common field of application of this method is the creep operated pressure equipment. In this case, the examination by means of replicas can reveal the microstructural configuration of the material and the damages due to microcavitation.