The Time-Temperature-Transformation (TTT) State Diagram and Cure

In the Fe-Ni system, although ordered FeNi and ordered Ni3Fe are experimentally well established, direct evidence for ordered Fe3Ni is unconvincing. Little experimental data for Fe3Ni exists because diffusion is sluggish at temperatures below 400°C and because alloys containing less than 29 wt% Ni undergo a martensitic transformation at room temperature. Fe-Ni phases in iron meteorites were examined in this study because iron meteorites have cooled at slow rates of about 10°C/106 years, allowing phase transformations below 400°C to occur. One low temperature transformation product, called clear taenite 2 (CT2), was of particular interest because it contains less than 30 wtZ Ni and is not martensitic. Because CT2 is only a few microns in size, the structure and Ni content were determined through electron diffraction and x-ray microanalysis. A Philips EM400T operated at 120 kV, equipped with a Tracor Northern 2000 multichannel analyzer, was used.

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Time-temperature-transformation (TTT) diagram of caustic calcined magnesia

CIM Journal ◽

10.15834/cimj.2015.1 ◽

2015 ◽

Vol 6 (1) ◽

pp. 42-50 ◽

Cited By ~ 1

Author(s):

K. Ebrahimi-Nasrabadi ◽

M. Barati ◽

P. W. Scott

Keyword(s):

Ttt Diagram ◽

Temperature Transformation

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Catapleiite behavior under heating and crystal structure of the product of its high-temperature transformation — the new phase Na6Zr3[Si9O27] with nine-membered rings of Si—O-tetrahedra

Zapiski RMO (Proceedings of the Russian Mineralogical Society) ◽

10.30695/zrmo/2018.1473.07 ◽

2018 ◽

Vol 147 (3) ◽

pp. 94-108

Author(s):

Ksenofontov D. A. ◽

◽

Grebenev V. V. ◽

Zubkova N. V. ◽

Pekov I. V. ◽

...

Keyword(s):

Crystal Structure ◽

High Temperature ◽

Temperature Transformation ◽

New Phase

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Induction period of the crystallization of silver nitrate solutions in ethylene glycol

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19912142 ◽

1991 ◽

Vol 56 (10) ◽

pp. 2142-2147

Author(s):

Ivo Sláma

Keyword(s):

Ethylene Glycol ◽

Silver Nitrate ◽

Induction Period ◽

Glass Forming Ability ◽

Transformation Theory ◽

Concentration Region ◽

Glass Forming ◽

Temperature Transformation ◽

Silver Nitrate Solutions ◽

Nitrate Solutions

The dependence of the induction period of crystallization on supercooling was examined for the silver nitrate-ethylene glycol system over the concentration region of silver nitrate lome fraction of 0 to 0.12. Addition of AgNO3 to ethylene glycol was found to increase considerably the critical induction period of crystallization, although to a lesser extent than Ca(NO3)2, CaCl2, ZnCl2, LiCl and LiNO3 do. The effect of these salts on the critical induction period of crystallization in dimethylsulfoxide, dimethylformamide, dimethylacetamide and methanol was compared in terms of the solvent-rich composition limit of the glass-forming ability. By using the TTT(Time-Temperature-Transformation) theory, it has been deduced that the effect of the salts on the critical induction period of crystallization of ethylene glycol is probably due to the different dependences of viscosity on their concentration in ethylene glyco in the supercooling region.

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The supercooling ability of calcium nitrate solutions in ethylene glycol

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19892711 ◽

1989 ◽

Vol 54 (10) ◽

pp. 2711-2714

Author(s):

Ivo Sláma ◽

Jarmila Malá

Keyword(s):

Thermal Stability ◽

Ethylene Glycol ◽

Induction Period ◽

Calcium Nitrate ◽

Transformation Diagram ◽

Temperature Transformation ◽

Thermal Stability Of ◽

Nitrate Solutions

The dependence of the induction period of crystallization on the supercooling was determined for the Ca(NO3)2-ethylene glycol system at mole fractions of the former from 0 to 0.049, and treated in terms of the TTT (Time-Temperature-Transformation) diagram. Addition of Ca(NO3)2 to ethylene glycol brings about a substantial increase in the critical induction period of crystallization. The thermal stability of glasses is discussed in terms of the shape and position of the TTT curves.

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Dynamic Transformation of Austenite at Temperatures above the Ae3

Materials Science Forum ◽

10.4028/www.scientific.net/msf.941.633 ◽

2018 ◽

Vol 941 ◽

pp. 633-638

Author(s):

John Joseph Jonas ◽

Clodualdo Aranas Jr. ◽

Samuel F. Rodrigues

Keyword(s):

Electron Microscopy ◽

Driving Force ◽

Energy Difference ◽

Accelerated Cooling ◽

Free Energy Difference ◽

Dynamic Transformation ◽

Plate Rolling ◽

Temperature Transformation ◽

Mn Steel ◽

Kinetics Of

Under loading above the Ae3 temperature, austenite transforms displacively into Widmanstätten ferrite. Here the driving force for transformation is the net softening during the phase change while the obstacle consists of the free energy difference between austenite and ferrite as well as the work of shear accommodation and dilatation during the transformation. Once the driving force is higher than the obstacle, phase transformation occurs. This phenomenon was explored here by means of the optical and electron microscopy of a C-Mn steel deformed above their transformation temperatures. Strain-temperature-transformation (STT) curves are presented that accurately quantify the amount of dynamically formed ferrite; the kinetics of retransformation are also specified in the form of appropriate TTRT diagrams. This technique can be used to improve the models for transformation on accelerated cooling in strip and plate rolling.

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