Fe-57 conversion electron Mossbauer spectroscopy of factors influencing Fe-Sn intermetallic phase formation in tinplated steel

The formation of intermetallic phases influences the properties of commercial alloys. CEMS can be used to reveal the presence of Fe-Sn intermetallics at the interface on tinplated steels. The work presented investigates the sensitivity of CEMS to detect intermetallics. Varying amounts of Fe-Sn intermetallics have been identified by CEMS having been produced by heat treating samples of tinplated steel at selected temperatures and times. The effect of surface roughness of the substrate on the Mossbauer signal has also been investigated. The intermetallic formation was found to reach a limiting value with increased heat treatment. Using CEMS, intermetallic formation was observed at temperatures as low as 190degreesC. Sample roughness was found to affect intermetallic formation and their observation using CEMS and GA-XRD.