An experimental and theoretical investigation of the effect of second-phase particles on grain growth during the annealing of hot-rolled AZ61 magnesium alloy

As an important fabrication process, annealing treatment is conducted to eliminate distortion in magnesium alloy sheets. Second-phase particles can provide nucleation sites for recrystallization grains, and the basal texture is related to the recrystallization behavior. Three experimental Mg-2Zn-based magnesium alloy sheets were investigated by the salt bath annealing process. Combined with variations in hardness softening, evolution of microstructure and basal texture, the effect of second-phase particles on microstructure evolution was analyzed. The results showed that the significant influence of size and distribution of second-phase particles on static recrystallization in magnesium alloy sheets was exhibited, which lead to the formation of two stages in the annealing process, combined with static recovery behavior. Second phase particles with coarse size were beneficial to recrystallization grains’ nucleation and increased recrystallization behavior in the initial stage of annealing. Second-phase particles with fine size inhibited recrystallization behavior and weakened the softening of hardness. The basal texture was weakened by second phase particles at the stage of recrystallization nucleation. The change in basal texture at the stage of grain growth was related to the size of second-phase particles. The regulation of basal texture enhancement can be envisioned by modifying second-phase particles.

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3D MС Simulation of Grain Growth Kinetics and the Zener Limit in Polycrystals

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.598.8 ◽

2014 ◽

Vol 598 ◽

pp. 8-12

Author(s):

K.R. Phaneesh ◽

Anirudh Bhat ◽

Gautam Mukherjee ◽

Kishore T. Kashyap

Keyword(s):

Monte Carlo ◽

Grain Growth ◽

Growth Kinetics ◽

Large Scale ◽

Volume Fraction ◽

Growth Exponent ◽

Cube Root ◽

Second Phase ◽

Two Phase ◽

Second Phase Particles

Large scale Potts model Monte Carlo simulation was carried on 3-dimensional square lattices of 1003 and 2003 sizes using the Metropolis algorithm to study grain growth behavior. Simulations were carried out to investigate both growth kinetics as well as the Zener limit in two-phase polycrystals inhibited in growth by second phase particles of single-voxel size. Initially the matrices were run to 10,000 Monte Carlo steps (MCS) to check the growth kinetics in both single phase and two-phase poly-crystals. Grain growth exponent values obtained as a result have shown to be highest (~ 0.4) for mono-phase materials while the value decreases with addition of second phase particles. Subsequently the matrices were run to stagnation in the presence of second phase particles of volume fractions ranging from 0.001to 0.1. Results obtained have shown a cube root dependence of the limiting grain size over the particle volume fraction thus reinforcing earlier 3D simulation efforts. It was observed that there was not much difference in the values of either growth kinetics or the Zener limit between 1003 and 2003 sized matrices, although the results improved mildly with size.

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Grain Growth during Annealing: Experiments and Modelling

Materials Science Forum ◽

10.4028/www.scientific.net/msf.715-716.611 ◽

2012 ◽

Vol 715-716 ◽

pp. 611-616 ◽

Cited By ~ 1

Author(s):

M. Candic ◽

Bao Hui Tian ◽

Christof Sommitsch

Keyword(s):

Grain Growth ◽

Second Phase ◽

Excellent Correlation ◽

Grain Sizes ◽

Second Phase Particles ◽

Different Temperatures ◽

Grain Growth Kinetics ◽

Parameter Approach ◽

Annealing Experiments ◽

Two Parameter

In the present work, for the description of grain coarsening, a probabilistic and a deterministic 2D cellular automaton simulation setup were developed. The results of the simulation have been validated by solution annealing experiments of austenitic stainless steel 304L (Fe-18Cr-8Ni) at different temperatures and times. Both cellular automata models show an excellent correlation between the experimental determined data and grain growth kinetics based upon considerations of temperature and second phase particles. Additionally, a two parameter approach of the probabilistic model was implemented, resulting in determining the grain sizes limiting normal and abnormal grains and accurate description of grain growth.

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Phase-field study of the effects of second-phase particles on abnormal grain growth

The Proceedings of The Computational Mechanics Conference ◽

10.1299/jsmecmd.2017.30.019 ◽

2017 ◽

Vol 2017.30 (0) ◽

pp. 019

Author(s):

Yoshihiro Suwa

Keyword(s):

Field Study ◽

Grain Growth ◽

Phase Field ◽

Abnormal Grain Growth ◽

Second Phase ◽

Second Phase Particles

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Assessment of Microstructure and Wear Resistance of Friction Stir Processed Cast Mg-Al-Zn Magnesium Alloy

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.787.442 ◽

2015 ◽

Vol 787 ◽

pp. 442-447 ◽

Cited By ~ 1

Author(s):

R. Jayaraman ◽

T. Balusamy ◽

A.K. Lakshminarayanan

Keyword(s):

Wear Resistance ◽

Magnesium Alloy ◽

Base Metal ◽

Second Phase ◽

Micro Hardness ◽

Friction Stir ◽

Second Phase Particles ◽

Metal Wear ◽

Pin On Disc ◽

Cast Magnesium

Microstructure, micro hardness and wear resistance of friction stir processed cast magnesium alloy are investigated in this work. Image analysis is used to differentiate the amount of phases present in the base metal and friction stir processed regions. Hardness mapping indicates that the frictions stir processed region has 64 % increase in microhardness compared to the base metal. Wear resistance was evaluated using pin-on-disc testing and it is found that the friction stir processed region has superior wear resistance compared to the base metal. Fine grains with uniformly distributed second phase particles are the reasons for improved microhardness and wear resistance of friction stir processed region.

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Characteristics of Deposition Precipitation Process in Production of High Strength and Low Carbon Steel in FTSR

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.886.128 ◽

2014 ◽

Vol 886 ◽

pp. 128-131

Author(s):

Zhuo Fei Song ◽

Shan Shan Feng ◽

Yun Li Feng

Keyword(s):

Solid State ◽

Low Carbon Steel ◽

High Strength ◽

Dynamical Analysis ◽

Precipitation Process ◽

Second Phase ◽

Low Carbon ◽

Second Phase Particles ◽

Thermodynamics And Dynamics ◽

Hot Rolled

Precipitation characteristics of second phase in HSLC steel produced by FTSR technology have been researched by TEM and EDS in this article. And preliminary research of precipitation conditions of second phase particles in thermodynamics and dynamics have been took. The results indicate that: there’re second phase particles precipitated dispersively in hot rolled HSLC steels by FTSR technology. These particles mainly contain particles of Al2O3、MnS and AlN. Thermo dynamical analysis declares that most of the Al2O3 and all of the MnS、 AlN particles are precipitated in solid state. That’s why the precipitation process is slowed down by the diffusion velocity of the elements in solid, and thinner particles are precipitated while the material is in solid state than in liquid state.

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