The Experts below are selected from a list of 2730 Experts worldwide ranked by ideXlab platform
K.e. Hensger - One of the best experts on this subject based on the ideXlab platform.
-
Determination and prediction of the inherited ferrite texture in a HSLA steel produced by compact strip production
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2001Co-Authors: B. Gardiola, Michel Humbert, Claude Esling, G. Flemming, K.e. HensgerAbstract:The ferrite and Residual Austenite textures were measured in a microalloyed (high strength low alloy, HSLA) steel produced by compact strip production, a process for the production of hot strips from a continuously cast slab using direct charging. The conditions of the thermomechanical rolling influence the texture and microstructure of Austenite and thus modify the mechanical behaviour of the final products, obtained after a γ to α phase transformation. The ferrite and Residual Austenite phases show strong texture gradients in the thickness of the sheet. Simulations of the thermomechanical rolling using the Taylor model allowed us to relate qualitatively the main trends of the surface and mid-thickness textures of the Austenite to the process. By modelling the phase transformation, the surface and mid-thickness inherited ferritic textures have been computed, without variant selection, from the Residual Austenite texture. These simulated textures are compared with the experimental ones and the texture inheritances are discussed.
Yvan Houbaert - One of the best experts on this subject based on the ideXlab platform.
-
Microstructure and texture of a lightly deformed TRIP-assisted steel characterized by means of the EBSD technique
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2006Co-Authors: Roumen Petrov, Leo Kestens, Anna Wasilkowska, Yvan HoubaertAbstract:Abstract The microstructural and textural changes after a tensile strain of 10% were observed by orientation contrast measurements in a TRIP-assisted steel. On the undeformed samples it was shown that the electron back scatter diffraction (EBSD) technique could be used successfully for determining the volume fraction of the microstructural constituents bainite, ferrite and Austenite, whereas after deformation only the BCC and FCC phases could be separated. The results show that the tensile strain of 10% gave rise to a drop in Residual Austenite content from 10 to 4%, which was also confirmed by magnetic measurements. The texture data showed only minor orientation rotations after 10% tensile strain for the BCC ferrite and bainite grains, whereas the Residual Austenite did show a significant texture change. By meticulously monitoring the local intra-granular misorientations it was concluded that the BCC phases (ferrite and bainite) took up the larger part of the nominal strain whereas the Residual Austenite primarily responded to the mechanical load by a partial (stress-induced) martensite transformation. Hence, the texture change observed in the Residual Austenite could be attributed to the orientation selective character of the phase transformation.
Rui Long - One of the best experts on this subject based on the ideXlab platform.
-
Artificial neural network prediction of retained Austenite content and impact toughness of high-vanadium high-speed steel (HVHSS)
Materials Science and Engineering: A, 2006Co-Authors: Xu Liujie, Jiandong Xing, Shizhong Wei, Yongzhen Zhang, Rui LongAbstract:Abstract The Residual Austenite content and impact toughness were measured after HVHSS were quenched at 900–1100 °C, and then tempered at 250–600 °C. By back-propagation (BP) networks, the non-linear relationships of the Residual Austenite contents (Ar) and impact toughness (Ak) versus quenching temperature and tempering temperature ( T 1, T 2) were established, respectively, on the base of dealing with the experimental data. The results show that the well-trained BP neural network can precisely predict the Residual Austenite contents and impact toughness according to quenching and tempering temperatures. The prediction results indicate Residual Austenite content decreases with decreasing quenching temperature or increasing tempering temperature, which results in decreasing impact toughness. But impact toughness takes on slightly increasing tendency at low quenching temperature and high tempering temperature because of the transformations of quench martensite to temper martensite. The prediction values have sufficiently mined the basic domain knowledge of heat treatment process. Therefore, a new way of optimizing heat treatment technique for controlling Residual Austenite content and predicting impact toughness was provided by the authors.
B. Gardiola - One of the best experts on this subject based on the ideXlab platform.
-
Determination and prediction of the inherited ferrite texture in a HSLA steel produced by compact strip production
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2001Co-Authors: B. Gardiola, Michel Humbert, Claude Esling, G. Flemming, K.e. HensgerAbstract:The ferrite and Residual Austenite textures were measured in a microalloyed (high strength low alloy, HSLA) steel produced by compact strip production, a process for the production of hot strips from a continuously cast slab using direct charging. The conditions of the thermomechanical rolling influence the texture and microstructure of Austenite and thus modify the mechanical behaviour of the final products, obtained after a γ to α phase transformation. The ferrite and Residual Austenite phases show strong texture gradients in the thickness of the sheet. Simulations of the thermomechanical rolling using the Taylor model allowed us to relate qualitatively the main trends of the surface and mid-thickness textures of the Austenite to the process. By modelling the phase transformation, the surface and mid-thickness inherited ferritic textures have been computed, without variant selection, from the Residual Austenite texture. These simulated textures are compared with the experimental ones and the texture inheritances are discussed.
Roumen Petrov - One of the best experts on this subject based on the ideXlab platform.
-
Microstructure and texture of a lightly deformed TRIP-assisted steel characterized by means of the EBSD technique
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2006Co-Authors: Roumen Petrov, Leo Kestens, Anna Wasilkowska, Yvan HoubaertAbstract:Abstract The microstructural and textural changes after a tensile strain of 10% were observed by orientation contrast measurements in a TRIP-assisted steel. On the undeformed samples it was shown that the electron back scatter diffraction (EBSD) technique could be used successfully for determining the volume fraction of the microstructural constituents bainite, ferrite and Austenite, whereas after deformation only the BCC and FCC phases could be separated. The results show that the tensile strain of 10% gave rise to a drop in Residual Austenite content from 10 to 4%, which was also confirmed by magnetic measurements. The texture data showed only minor orientation rotations after 10% tensile strain for the BCC ferrite and bainite grains, whereas the Residual Austenite did show a significant texture change. By meticulously monitoring the local intra-granular misorientations it was concluded that the BCC phases (ferrite and bainite) took up the larger part of the nominal strain whereas the Residual Austenite primarily responded to the mechanical load by a partial (stress-induced) martensite transformation. Hence, the texture change observed in the Residual Austenite could be attributed to the orientation selective character of the phase transformation.
