Modeling recovery and recrystallization kinetics in cold-rolled Ti-Nb stabilized interstitial-free steel

Journal Article · Fri Nov 01 04:00:00 EST 1996 · Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science

DOI:https://doi.org/10.1007/BF02595434· OSTI ID:413277

Mukunthan, K ^[1]; Hawbolt, E B ^[2]

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1. BHP Research, Wallsend, New South Wales (Australia). New Castle Labs.
2. Univ. of British Columbia, Vancouver, British Columbia (Canada). Dept. of Metals and Materials engineering

The recovery and recrystallization kinetics in an 80 pct cold-rolled Ti-Nb stabilized interstitial-free (IF) steel have been characterized for isothermal (500 to 760 C) and continuous heating (0.025 C s{sup {minus}1} to 20.2 C s{sup {minus}1}) annealing. Isothermal recovery kinetics, as monitored by {l_brace}220{r_brace} X-ray peak resolution measurements, were described using a semiempirical logarithmic equation. The IF steel recovered relatively easily, with approximately 45 to 60 pct of the total peak resolution occurring prior to the onset of recrystallization. An iterative procedure was adopted to separate the diffraction effects associated with the concurrent recovery and recrystallization processes. Microstructural observations indicated that the recrystallization event was heterogeneous, with preferential nucleation and early site saturation at grain boundaries in the cold-rolled material. Isothermal recrystallization kinetics, determined by quantitative metallography, were described using the Johnson-Mehl-Avrami-Kolmogorov (JMAK) and Speich-Fisher (SF) relationships. Recovery and recrystallization kinetics during continuous heating have been modeled using the isothermal kinetic parameters, assuming the validity of the principle of additivity. The results were validated by experimental measurements obtained at heating rates simulating both batch and continuous annealing. Although the Scheil additivity equation overestimated the recrystallization start time for continuous heating conditions, the associated higher temperature and more rapid initial recrystallization resulted in similar overall kinetics.

• Sponsoring Organization: Natural Sciences and Engineering Research Council of Canada, Ottawa, ON (Canada)
• OSTI ID: 413277
• Journal Information: Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science, Journal Name: Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science Journal Issue: 11 Vol. 27; ISSN 1073-5623; ISSN MMTAEB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ACTIVATION ENERGY
ANNEALING
CHEMICAL COMPOSITION
COLD WORKING
GRAIN BOUNDARIES
LINE BROADENING
MATHEMATICAL MODELS
METALLOGRAPHY
NIOBIUM ALLOYS
NUCLEATION
RECRYSTALLIZATION
SIMULATION
STEELS
TITANIUM ALLOYS
VALIDATION
X-RAY DIFFRACTION