401 Low Temperature Bainite Transformation Behavior and Features of Transformed Microstructure

The objective of the present article is to study the influence of TiB2 addition on the transformation behavior of yttria stabilized tetragonal zirconia polycrystals (Y-TZP). A range of TZP(Y)–TiB2 composites with different zirconia starting powder grades and TiB2 phase contents (up to 50 vol%) were processed by the hot-pressing route. Thermal expansion data, as obtained by thermo-mechanical analysis were used to assess the ZrO2 phase transformation in the composites. The thermal expansion hysteresis of the transformable ceramics provides information concerning the transformation behavior in the temperature range of the martensitic transformation and the low-temperature degradation. Furthermore, the transformation behavior and susceptibility to low-temperature degradation during thermal cycling were characterized in terms of the overall amount and distribution of the yttria stabilizer, zirconia grain size, possible dissolution of TiB2 phase, and the amount of residual stress generated in the Y-TZP matrix due to the addition of titanium diboride particles. For the first time, it is demonstrated in the present work that the thermally induced phase transformation of tetragonal zirconia in the Y-TZP composites can be controlled by the intentional addition of the monoclinic zirconia particles into the 3Y-TZP matrix.

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Transformation behavior of Ni–Mn–Ga in the low-temperature limit

Journal of Physics Condensed Matter ◽

10.1088/0953-8984/24/27/276004 ◽

2012 ◽

Vol 24 (27) ◽

pp. 276004 ◽

Cited By ~ 1

Author(s):

J I Pérez-Landazábal ◽

V Recarte ◽

V Sánchez-Alarcos ◽

V A Chernenko ◽

J M Barandiarán ◽

...

Keyword(s):

Low Temperature ◽

Temperature Limit ◽

Transformation Behavior

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Effects of lanthanum on bainite transformation behavior in Mn–Cr–Mo rail steel

Journal of Materials Research ◽

10.1557/s43578-021-00220-7 ◽

2021 ◽

Author(s):

Xirong Bao ◽

Jun’an Wang

Keyword(s):

Rail Steel ◽

Transformation Behavior ◽

Bainite Transformation

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Effect of Ausforming Temperature on Bainite Transformation of High Carbon Low Alloy Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.817.454 ◽

2015 ◽

Vol 817 ◽

pp. 454-459 ◽

Cited By ~ 3

Author(s):

Jian Guo He ◽

Ai Min Zhao ◽

Huang Yao ◽

Chao Zhi ◽

Fu Qing Zhao

Keyword(s):

Low Temperature ◽

Alloy Steel ◽

Retained Austenite ◽

Volume Fraction ◽

Transformation Rate ◽

Low Alloy Steel ◽

High Carbon ◽

Bainite Transformation ◽

Electron Backscattered Diffraction ◽

In Situ Experiments

The effect of ausforming temperature on bainite transformation of high carbon low alloy steel was studied by in situ experiments using a Gleeble 3500 thermal and mechanical testing system. Morphology and crystallography of ausforming bainite were examined by scanning electron microscopy (SEM) and electron backscattered diffraction (EBSD). It has been found that deformation at all temperatures range from 230°C to 600°C can accelerate low temperature bainite transformation, and transformation rate increased with deformation temperature reduced. Quantitative X-ray analysis shows that the volume fraction of retained austenite was about 35.84% after deformation and isothermal transformation for 20 hours, it was approximately the same amount with austempering bainite transformation process (no strain) which austenite volume fraction was about 32.01%. Low temperature bainite formation can be accelerated with a smaller increase amount of retained austenite by deformation at a low temperature range of 230~600 oC.

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