| Issue |
Microsc. Microanal. Microstruct.
Volume 6, Number 5-6, October / December 1995
|
|
|---|---|---|
| Page(s) | 633 - 646 | |
| DOI | https://doi.org/10.1051/mmm:1995153 | |
DOI: 10.1051/mmm:1995153
TEM-EDS Characterization of Second Phases in Ferritic Steels
Susanna Matera et Ettore AnelliCentro Sviluppo Materiali S.P.A, P.O. Box 10747, Roma-EUR, Italy
Abstract
TEM/STEM-EDS methods for the quantitative assessment of
geometrical parameters, chemical composition and crystal
structure of second phase particles are reviewed. Significant
applications are discussed with regard to different ferritic
steels: Interstitial Free (IF) steel for deep drawing,
electrical 1%Si steel and enameling steel. After short term
isothermal annealing, a Ti-containing IF steel exhibited Ti(C,N)
precipitates that were finer and more frequent than
.
Ti(C,N) was a preferential site for
nucleation. The
experimental results were compared with calculations by a
mathematical model of precipitation. Analysis of second phase
particles in an electrical 1% Si steel after isothermal
annealing allowed evaluation of the inhibition factor for grain
growth. The abnormal grain growth in this steel was mainly due
to dissolution of
and Ostwald ripening of (Mn,Cu)S and
Ti(C,N) with AlN. Quantitative investigation of precipitates in
an enameling steel, together with hydrogen permeation
measurements, showed that interstitial sites at the surface of
coherent 
-Ti(C,N) precipitates act as efficient traps for
hydrogen atoms.
8130M - Precipitation.
8140G - Other heat and thermomechanical treatments.
6155H - Crystal structure of specific alloys.
6475 - Solubility, segregation, and mixing.
6480E - Stoichiometry and homogeneity.
6630F - Self diffusion in solid metals, semimetals, and alloys.
Key words
annealing -- crystal structure -- diffusion -- grain growth -- nucleation -- precipitation -- scanning transmission electron microscopy -- steel -- stoichiometry -- transmission electron microscopy -- X ray chemical analysis -- grain growth -- second phases -- ferritic steels -- TEM STEM EDS methods -- quantitative assessment -- geometrical parameter -- chemical composition -- crystal structure -- second phase particles -- review -- interstitial free steel -- deep drawing -- electrical steel -- enameling steel -- short term isothermal annealing -- Ti containing IF steel -- Ti C,N precipitates -- Ostwald ripening -- Ti sub 4 C sub 2 S sub 2 nucleation -- precipitation -- isothermal annealing -- inhibition factor
© EDP Sciences 1995