Results 121 to 130 of about 14,484 (149)

Isothermal phase transformations of a dental porcelain

Dental Materials, 2005
The purpose of this investigation was to determine if the change in the leucite weight fraction during an isothermal heat treatment could be estimated by observing the deformation of PFM strips in a high-heating-rate, computer-controlled bending beam viscometer (BBV).Specimens of a commercial body porcelain were fired according to the manufacturer's ...
S Warren, Twiggs, J Rodway, Mackert, Amalia L, Oxford, Janet W, Ergle, Petra E, Lockwood   +4 more
openaire   +2 more sources

Phase transformations in metastable β′ CuZn alloys: II: Isothermal transformations

Scripta Metallurgica, 1973
Abstract The present investigation was carried out with the primary purpose of establishing the nature of the isothermal β′ → α1 transformation in Cu-Zn alloys containing ~40 wt.% Zn. The morphology, habit plane, shape deformation, crystal structure, substructure, and orientation relationship of the plate shaped α1 transformation product have been ...
I Cornelis, C.M Wayman
openaire   +1 more source

Additivity rule, isothermal and non-isothermal transformations on the basis of an analytical transformation model

Acta Materialia, 2007
Abstract In the present work, the “additivity rule” was proved to be compatible with an analytical transformation model assuming mixed nucleation (with site saturation and continuous nucleation as two extremes), for some specified conditions. Combining the analytical model with numerical calculations, it is practicable to allow a conversion of ...
F LIU, C YANG, G YANG, Y ZHOU
openaire   +1 more source

Isothermal transformation of high-nitrogen austenite

Scripta Materialia, 2007
The isothermal transformation of high-nitrogen austenite occurring at 225 °C was found to be a γ → α-Fe + γ′-Fe 4 N upper bainitic one, which inhomogeneously and preferentially occurred at the grain boundaries and at the dislocations in the interior of the prior austenite grains, producing a microstructure composed of (α-Fe + γ′-Fe 4 N) bainitic ...
Dongling Jiao, C.P. Luo, Jiangwen Liu
openaire   +1 more source

Relationship between non-isothermal transformation curves and isothermal and non-isothermal kinetics

Acta Materialia, 2005
A mathematical method is presented to obtain an isothermal transformation curve from a continuous cooling transformation (CCT) curve. It can also be used for transformations that occur during continuous heating rather than continuous cooling. The method is applied to nucleation and growth transformations and to grain growth.
openaire   +1 more source

Isothermal bainite transformation in low-alloy steels: Mechanism of transformation

Acta Materialia, 2021
Abstract Effect of carbon concentration of parent austenite on isothermal transformation to bainite has been studied. It has been shown that when the carbon concentration of parent austenite is low and the transformation temperature is higher than the Zener ordering temperature, the carbon content of bainitic ferrite is low.
Ravi Ranjan, Shiv Brat Singh
openaire   +1 more source

Isothermal nanocrystallization kinetics during polymorphic transformation

Journal of Non-Crystalline Solids, 2009
Abstract The experimental value of Avrami exponent during polymorphic nanocrystallization deviates from the theoretical prediction of the Kolmogorov–Johnson–Mehl–Avrami (KJMA) isothermal kinetics. The assumption of negligible nuclei volume, implicit in KJMA, is violated for all such transformations involving nano-sized grains.
I. Sinha, R.K. Mandal
openaire   +1 more source

Mathematical treatment of non-isothermal transformations

Materials Science and Technology, 1987
AbstractPrediction of transformation kinetics in steel at varying temperature is of great practical importance in different areas of heat treatment and material science. By formal generalization of the conventional isothermal kinetic functions applied for characterizing thermally activated processes, new types of kinetic function were generated which ...
T. Réti, M. Gergely, P. Tardy
openaire   +1 more source

Nucleation of the isothermal martensitic transformation

Acta Metallurgica, 1969
Abstract By means of quantitative metallography and electrical-resistivity measurements, the initial nucleation rates of the isothermal martensitic transformation were determined in a series of three iron, 23–25 wt.% nickel, 2–3 wt. % manganese alloys as a function of austenitic grain size and reaction temperature, taking autocatalytic effects into ...
S.R Pati, Morris Cohen
openaire   +1 more source

Isothermal martensitic transformation in polycrystalline Ni50Mn29Ga21

Journal of Alloys and Compounds, 2010
Abstract The isothermal transformation behaviour of polycrystalline Ni 50 Mn 29 Ga 21 magnetic shape memory alloy is investigated by measuring the saturation magnetisation as a function of time and temperature. The results are analysed within the framework of the Johnson–Mehl–Avrami–formalism.
C. Hürrich, S. Roth, M. Pötschke, B. Rellinghaus, L. Schultz   +4 more
openaire   +1 more source