scholarly journals A Study on the Hall–Petch Relationship and Grain Growth Kinetics in FCC-Structured High/Medium Entropy Alloys

Entropy ◽  
2019 ◽  
Vol 21 (3) ◽  
pp. 297 ◽  
Author(s):  
Yung-Chien Huang ◽  
Che-Hsuan Su ◽  
Shyi-Kaan Wu ◽  
Chieh Lin
Keyword(s):  
Grain Size ◽  
Grain Growth ◽  
Growth Kinetics ◽  
Lattice Distortion ◽  
Kinetic Constant ◽  
Growth Exponent ◽  
Hardness Variation ◽  
Modulus Difference ◽  
Cold Rolled ◽  
Grain Growth Kinetics

The recrystallization behavior, grain growth kinetics, and corresponding hardness variation of homogenized and 80% cold-rolled FeCoNiCrPd, FeCoNiCrMn, and their quaternary/ternary FCC-structured high/medium entropy alloys (H/MEAs) annealed under different conditions were investigated. Experimental results indicate that the grain size and hardness of these H/MEAs follow the Hall–Petch equation, with the Hall–Petch coefficient KH value being mainly dominated by the alloy’s stacking fault energy and shear modulus. The FeCoNiCrPd alloy exhibits the highest hardness of the H/MEAs at the same grain size due to the largest Young’s modulus difference between Cr and Pd. The grain growth exponent n, kinetic constant k, and activation energy for grain growth QG of all H/MEAs are calculated. The k can be expressed by the Arrhenius equation with QG, which is attributed to the diffusion rate. The results demonstrate that the QG values of these H/MEAs are much higher than those of conventional alloys; most notable is FeCoNiCrPd HEA, which has an unusually lattice distortion effect that hinders grain growth.

The Influence of Grain Size Determination Method on Grain Growth Kinetics Analysis

2015 ◽  
Vol 17 (11) ◽  
pp. 1598-1607 ◽  
Author(s):  
Leyla Hashemi-Sadraei ◽  
S. Ebrahim Mousavi ◽  
Enrique J. Lavernia ◽  
Julie M. Schoenung
Keyword(s):  
Grain Size ◽  
Grain Growth ◽  
Growth Kinetics ◽  
Size Determination ◽  
Determination Method ◽  
Kinetics Analysis ◽  
Grain Growth Kinetics

Effects of Solubility Limit and the Presence of Ultra-Fine Al6Fe on the Kinetics of Grain Growth in Dilute Al-Fe Alloys

2007 ◽  
Vol 550 ◽  
pp. 339-344 ◽  
Author(s):  
Shigeo Saimoto ◽  
Hai Ou Jin
Keyword(s):  
Grain Size ◽  
Cold Rolling ◽  
Grain Growth ◽  
Solubility Limit ◽  
Rolled Sheet ◽  
Migration Rates ◽  
Cold Rolled ◽  
Fe Alloys ◽  
Grain Growth Kinetics ◽  
Kinetics Of

A nominally pure Al slab was thermo-mechanically treated to result in a near random texture of 90 m grain size. Subsequent cold rolling with intermediate anneals at 230, 275, and 300°C reduced the Fe solute to near equilibrium compositions below 0.5 ppm atomic. The final cold rolled sheet continuously recrystallized; grain growth of this structure is reported. A grain-growth kinetics mapping was generated, correlating the parameters of Fe-in-Al solubility limit, Fe diffusivities in the grain boundaries and the Al lattice and the activation energies for migration rates.

Non-Isothermal Austenite Grain Growth Kinetics in the HAZ of a Microalloyed X-80 Linepipe Steel

2011 ◽  
Vol 172-174 ◽  
pp. 809-814 ◽  
Author(s):  
Kumkum Banerjee ◽  
Michel Perez ◽  
Matthias Militzer
Keyword(s):  
Grain Size ◽  
Heating Rate ◽  
Grain Growth ◽  
Growth Kinetics ◽  
Electron Microscopic ◽  
Austenite Grain Size ◽  
Austenite Grain ◽  
Grain Growth Kinetics ◽  
Austenite Grain Growth ◽  
Linepipe Steel

Non-isothermal austenite grain growth kinetics under the influence of several combinations of Nb, Ti and Mo containing complex precipitates has been studied in a microalloyed linepipe steel. The goal of these studies is the development of a grain growth model to predict the austenite grain size in the weld heat affected zone (HAZ). A detailed electron microscopic investigations of the as-received steel proved the presence of Ti-rich, Nb-rich and Mo-rich precipitates. Inter and intragranular precipitates of ~5-150 nm have been observed. The steel has been subjected to austenitizing heat treatments to selected peak temperatures of 950, 1150 and 1350°C at various heating rates of 10, 100 and 1000°C/s. Thermal cycles have been found to have a strong effect on the final austenite grain size. The increase in heating rate from 100 to 1000°C/s has a negligible difference in the austenite grain size irrespective of the austenitizing temperature. However, the increase in grain size has been noticed at 10°C/s heating rate for all the austenitizing temperatures. The austenite grain growth kinetics have been explained taking into account the austenite growth in the presence of precipitates.

Grain Growth in Nb-Alloyed Stainless Steel of AISI 347 during Heating

2013 ◽  
Vol 753 ◽  
pp. 345-348 ◽  
Author(s):  
Hai Wen Luo ◽  
Han Dong ◽  
Ling Feng Chen
Keyword(s):  
Activation Energy ◽  
Stainless Steel ◽  
Grain Growth ◽  
Growth Kinetics ◽  
Isothermal Holding ◽  
Growth Exponent ◽  
Microalloyed Steels ◽  
Nb Content ◽  
Grain Growth Kinetics ◽  
Kinetics Of

Grain growth kinetics in an AISI 347 stainless steel with Nb content up to 0.7%wt was studied during the isothermal holding in the temperature range of 1100-1270°C for various periods. Abnormal grain growth was observed even in the presence of a large amount of precipitates. The kinetics of normal grain growth was tracked by metallographic measurements and fitted by the classical modeling, which led to two important parameters of activation energy Q and growth exponent n derived. Both of them are larger than the usual values for grain growth in the Nb-microalloyed steels due to the much larger content of Nb in the present steel.

scholarly journals Computer simulation of grain growth kinetics with solute drag

1999 ◽  
Vol 14 (3) ◽  
pp. 1113-1123 ◽  
Author(s):  
D. Fan ◽  
S. P. Chen ◽  
Long-Qing Chen
Keyword(s):  
Grain Boundary ◽  
Grain Growth ◽  
Growth Kinetics ◽  
Driving Force ◽  
Boundary Energy ◽  
Solute Drag ◽  
Lattice Diffusion ◽  
Diffuse Interface ◽  
Growth Exponent ◽  
Grain Growth Kinetics

The effects of solute drag on grain growth kinetics were studied in two-dimensional (2D) computer simulations by using a diffuse-interface field model. It is shown that, in the low velocity/low driving force regime, the velocity of a grain boundary motion departs from a linear relation with driving force (curvature) with solute drag. The nonlinear relation of migration velocity and driving force comes from the dependence of grain boundary energy and width on the curvature. The growth exponent m of power growth law for a polycrystalline system is affected by the segregation of solutes to grain boundaries. With the solute drag, the growth exponent m can take any value between 2 and 3, depending on the ratio of lattice diffusion to grain boundary mobility. The grain size and topological distributions are unaffected by solute drag, which are the same as those in a pure system.

Ways of Numerical Prediction of Austenitic Grain Size in Heat-Affected Zone of Welds

2014 ◽  
Vol 1029 ◽  
pp. 25-30 ◽  
Author(s):  
Jaromír Moravec ◽  
Josef Bradáč ◽  
Iva Nováková
Keyword(s):  
Grain Size ◽  
Grain Growth ◽  
Growth Kinetics ◽  
Temperature Deformation ◽  
Structure Changes ◽  
Predicted Values ◽  
Definition Of ◽  
Grain Growth Kinetics ◽  
Austenitic Grain Size

In the present time there is a clear effort to achieve the most exact mathematical description of the behaviour of “Hi-tech” materials when exposed to temperature and stress loading. Besides the common numerically predicted values such as temperature, deformation and stress fields, or as the case may be structure changes during phase transformations, demands for prediction of the austenitic grain size in HAZ of welds become more and more frequent. That is why the present submission deals with the analysis of the determination of the grain size and grain growth kinetics of HR3C single-phase austenitic steel using the Monte Carlo Potts method. The procedure of obtaining the input data for numerical simulations will be demonstrated on HR3C steel, including the determination of grain growth kinetics and definition of all the parameters needed for a computational model. Results from the numerical simulation in Sysweld program will be then compared against the real experiment for a multi-layered weld made on HR3C tube.

Theory of Grain Growth in the Presence of Atoms Drag Effects

2007 ◽  
Vol 558-559 ◽  
pp. 1005-1012 ◽  
Author(s):  
Giuseppe Carlo Abbruzzese ◽  
Massimiliano Buccioni
Keyword(s):  
Grain Size ◽  
Size Distribution ◽  
Grain Growth ◽  
Grain Size Distribution ◽  
Growth Kinetics ◽  
Considerable Change ◽  
Zener Drag ◽  
Distribution Shape ◽  
Grain Growth Kinetics ◽  
Grain Boundary Movement

The statistical model of grain growth is able to predict the effect of Zener drag on the grain size distribution evolution and on grain growth kinetics [1, 2]. This paper, in the same framework, will treat the case of atoms drag on grain boundary movement. The mechanism by which atoms drag operates is significantly different by that of Zener. The corresponding peculiar features will result in a specific grain size distribution evolution with considerable change of grain growth kinetics and distribution shape from that of normal grain growth case as a function of the intensity of the pinning conditions.

Austenite Grain Growth Kinetics during Continuous Heating of a Microalloyed X-80 Linepipe Steel

2012 ◽  
Vol 715-716 ◽  
pp. 292-296
Author(s):  
Kumkum Banerjee ◽  
Michel Perez ◽  
Matthias Militzer
Keyword(s):  
Grain Size ◽  
Heating Rate ◽  
Grain Growth ◽  
Growth Kinetics ◽  
Continuous Heating ◽  
Austenite Grain Size ◽  
Austenite Grain ◽  
Grain Growth Kinetics ◽  
Austenite Grain Growth ◽  
Linepipe Steel

Non-isothermal austenite grain growth kinetics has been studied in a microalloyed linepipe steel with complex precipitates containing Ti, Nb and/or Mo. The goal of these experimental studies is to provide the basis for the development of a grain growth model to predict the austenite grain size evolution in the weld heat affected zone (HAZ). Detailed electron microscopic investigations of the as received steel proved the presence of Ti-rich, Nb-rich and Mo-rich precipitates. The steel was subjected to austenitizing heat treatments to selected peak temperatures of 950, 1150 and 1350 °C at heating rates of 10, 100 and 1000 °C/s, respectively. Thermal cycles have been found to have a strong effect on the austenite grain size. Austenite grain sizes increase with peak temperature and decreasing heating rate. However, the increase in heating rate from 100 to 1000 °C/s has a negligible effect on the austenite grain size. The observed austenite grain growth kinetics can be explained taking into account the potential dissolution of Nb-rich precipitates.

Sign in / Sign up

Export Citation Format

Share Document