Carbon-free martensite
formed by casting a CoFeSi alloy into a copper mold. Several generations of martensite needles are clearly distinguishable, and the former austenite grains can be identified. Metallographic specimen etched with color etching agent V2A-Beize and imaged in reflected light microscope.
Submitted by: Felix Trauter, Materials Research Institute, Aalen University, Aalen, Germany