Current PM literature for engineers and users

Abstract

Transmission electron microscopy (TEM) as well as corresponding analytical techniques, such as high resolution TEM (HRTEM), energy dispersive X-ray (EDX) analysis, electron energy loss spectroscopy (EELS) and elemental mapping via a Gatan imaging filter (GIF), have been used to study the complex precipitation morphology of the commercial Fe–Cr–Al based oxide dispersion strengthened (ODS) alloy PM 2000. Formation of homogeneously distributed Y–Al–O ODS particles from Y₂O₃ added to the metal powder is shown. Besides these ODS particles, a large amount of complex Y–Al–O/Al₂O₃ and Y–Al–O/TiC as well as pure Al₂O₃ inclusions with sizes significantly larger than ODS particles have been identified. A typical feature is the growth of Al₂O₃ and Y–Al–O particles on the surface of small Ti(C,N) nuclei. Some implications of the results obtained from the mechanical properties of PM 2000 steel are discussed.