Phase transformations in the Zr-rich part of the Zr-Fe system resulting from heat treatment and plastic deformation

Journal Article · Thu Jan 01 04:00:00 EST 1987 · Metall. Trans., A; (United States)

DOI:https://doi.org/10.1007/BF02646218· OSTI ID:6953469

Weiss, B Z; Bamberger, M; Stupel, M M

Phases and phase transformations occurring in the Zr-rich part of the Zr-Fe system during heat treatment and plastic deformation were identified by means of Mossbaueer spectroscopy and X-ray diffraction analysis. Low iron alloys (<0.02 wt pct Fe) undergo a complete BETA..--> cap alpha../sub m/ reaction (martensitic type) on quenching. For higher iron content alloys (0.02 to 0.25 wt pct Fe) the BETA..--> cap alpha../sub m/ transformation is accompanied by formation of metastable intermediate phase designated theta. The iron concentration of theta-phase is much higher than of ..cap alpha..Zr(Fe). During the aging process, at the outset of the equilibrium state, the theta-phase disappears by transforming to Zr/sub 2/Fe intermetallic. Cold rolling of quenched (..cap alpha../sub m/+theta) specimens leads to formation of the athermal ..omega..-phase. Presence of the intermediate theta-phase seems to be a prerequisite for the athermal ..omega..-phase formation. A decrease in specific volume (..delta..V/sub theta/<0) accompanying the ..cap alpha -->..theta transition was suggested as a possible mechanism of the ..cap alpha -->..theta transformation. Mossbauer parameters for the thermal and athermal ..omega..-phase were determined. Presence of theta and athermal ..omega..-phases were identified by Mossbauer spectroscopy only, being undetectable by X-ray diffraction, because of their minute quantities. Solubility of iron in the ..cap alpha.. Ar(Fe) solid solution was determined in the range of temperatures 713 to 943 K (440 to 670/sup 0/C).

• Research Organization: Dept. of Materials Engineering, Technion, Israel Institute of Technology, Haifa (IL)
• OSTI ID: 6953469
• Journal Information: Metall. Trans., A; (United States), Journal Name: Metall. Trans., A; (United States) Vol. 18A:1; ISSN MTTAB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals &amp; Alloys-- Structure &amp; Phase Studies
ALLOYS
CARBON ADDITIONS
COHERENT SCATTERING
CRYSTAL-PHASE TRANSFORMATIONS
DEFORMATION
DIFFRACTION
HEAT TREATMENTS
IRON ALLOYS
MARTENSITE
MOESSBAUER EFFECT
PHASE STUDIES
PHASE TRANSFORMATIONS
SCATTERING
SOLUBILITY
X-RAY DIFFRACTION
ZIRCONIUM ALLOYS