Sub-Boundary Mobilities during Recovery of Binary Al-Mn Alloys

2012 ◽  
Vol 715-716 ◽  
pp. 725-731
Author(s):  
Fabrice Barou ◽  
Claire Maurice ◽  
Jean Marie Feppon ◽  
Julian H. Driver
Keyword(s):  
Grain Size ◽  
Dislocation Climb ◽  
Average Growth ◽  
Subsequent Recovery ◽  
Grain Sizes ◽  
Standard Relation ◽  
Growth Laws ◽  
Logarithmic Law ◽  
Kinetics Of ◽  
Evolution With Time

Two, high purity, Al-0.1 and 0.3wt%Mn alloys have been cold deformed in plane strain compression to strains of order 1.8 and the kinetics of subsequent recovery by sub-grain coarsening during annealing at 150-300°C measured by high resolution FEG-SEM EBSD. Accurate sub-grain size and misorientation distributions and their evolution with time and temperature have been determined. The average growth rates are then used to estimate the sub-grain boundary mobilities. Growth is analyzed by two well-known growth laws for the average sub-grain size δ (t): i) the standard relation for grain growth: where the exponent n takes values of 2-8 and ii) the relation proposed by Nes for dislocation climb in sub-grain walls: It is shown that the latter relation gives a better fit with the data in terms of the time and temperature dependence of the sub-grain sizes. In particular the activation energies for the logarithmic law are much closer to the values expected for solute-controlled movement of sub-boundaries.

Kinetics of the C49 TO C54 Phase Transformation in TiSi2 thin Films on Deep-Sub-Micron Lines

1995 ◽  
Vol 402 ◽  
Author(s):  
J. A. Kittl ◽  
D. A. Prinslow ◽  
P. P Apte ◽  
M. F. Pas
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Phase Transformation ◽  
Full Time ◽  
Two Dimensional ◽  
One Dimensional ◽  
Grain Sizes ◽  
Nucleation Sites ◽  
Dimensional Growth ◽  
Kinetics Of

AbstractThe kinetics of the TiSi2 C49 to C54 phase transformation in thin films on patterned deepsub- micron lines, were studied to obtain the full time, temperature and linewidth dependence of the fraction transformed during rapid thermal annealing. A Johnson-Mehl-Avrami kinetic analysis was performed, obtaining Avrami exponents of 0.8±0.2 for all sub-micron lines and 1. 9±0.2 for a 40 μm side square structure, indicating heterogeneous nucleation followed by one dimensional growth for the narrow lines, and two dimensional growth for the square structure. The activation energy, of 3.9 eV, was independent of linewidth in the sub-micron range. Transformation times increased dramatically for decreasing linewidth, as the linewidth approached the grain size of the starting C49 phase. A kinetic model based on the density of nucleation sites as a function of linewidth and C49 grain size is proposed and shown to fit the data, for samples with two different C49 grain sizes.

scholarly journals Experimental grain growth of quartz aggregates under wet conditions and its application to deformation in nature

2019 ◽  
Author(s):  
Junichi Fukuda ◽  
Hugues Raimbourg ◽  
Ichiko Shimizu ◽  
Kai Neufeld ◽  
Holger Stünitz
Keyword(s):  
Grain Size ◽  
Grain Growth ◽  
Growth Parameters ◽  
Growth Exponent ◽  
High Porosity ◽  
Grain Sizes ◽  
Two Samples ◽  
Growth Laws ◽  
Water Fugacity ◽  
Quartz Aggregates

Abstract. The grain growth of quartz was investigated using two samples of quartz (powder and quartzite) with water under pressure and temperature conditions of 1.0–2.5 GPa and 800–1100 °C. The compacted powder preserved a large porosity, which caused a slower grain growth than in the dense quartzite. We assumed a grain-growth law of dn-d0n = k0 fH2Or exp⁡(−Q/RT)t with grain size d (µm) at time t (second), initial grain size d0 (µm), growth exponent n, a constant k0 (µmn MPa−r s−1), water fugacity fH2O (MPa) with the exponent r, activation energy Q (kJ/mol), gas constant R, and temperature T in Kelvin. The parameters we obtained were n = 2.5 ± 0.4, k0 = 10−8.8 ± 1.4, r = 2.3 ± 0.3, and Q = 48 ± 34 for the powder, and n = 2.9 ± 0.4, k0 = 10−5.8 ± 2.0, r = 1.9 ± 0.3, and Q = 60 ± 49 for the quartzite. The grain-growth parameters obtained for the powder may be of limited use because of the high porosity of the powder with respect to crystalline rocks, even if the differences between powder and quartzite vanish when grain sizes reach ~ 70 µm. Extrapolation of the grain-growth laws to natural conditions indicates that the contribution of grain growth to plastic deformation in the middle crust may be small. However, grain growth might become important for deformation in the lower crust when the strain rate is

scholarly journals Experimental grain growth of quartz aggregates under wet conditions and its application to deformation in nature

Solid Earth ◽  
2019 ◽  
Vol 10 (3) ◽  
pp. 621-636 ◽  
Author(s):  
Junichi Fukuda ◽  
Hugues Raimbourg ◽  
Ichiko Shimizu ◽  
Kai Neufeld ◽  
Holger Stünitz
Keyword(s):  
Grain Size ◽  
Grain Growth ◽  
Growth Parameters ◽  
Growth Exponent ◽  
High Porosity ◽  
Natural Conditions ◽  
Grain Sizes ◽  
Growth Laws ◽  
Water Fugacity ◽  
Quartz Aggregates

Abstract. Grain growth of quartz was investigated using two quartz samples (powder and novaculite) with water under pressure and temperature conditions of 1.0–2.5 GPa and 800–1100 ∘C. The compacted powder preserved a substantial porosity, which caused a slower grain growth than in the novaculite. We assumed a grain growth law of dn-d0n=k0fH2Orexp⁡(-Q/RT)t with grain size d (µm) at time t (seconds), initial grain size d0 (µm), growth exponent n, a constant k0 (µmn MPa−r s−1), water fugacity fH2O (MPa) with the exponent r, activation energy Q (kJ mol−1), gas constant R, and temperature T in Kelvin. The parameters we obtained were n=2.5±0.4, k0=10-8.8±1.4, r=2.3±0.3, and Q=48±34 for the powder and n=2.9±0.4, k0=10-5.8±2.0, r=1.9±0.3, and Q=60±49 for the novaculite. The grain growth parameters obtained for the powder may be of limited use because of the high porosity of the powder with respect to crystalline rocks (novaculite), even if the differences between powder and novaculite vanish when grain sizes reach ∼70 µm. Extrapolation of the grain growth laws to natural conditions indicates that the contribution of grain growth to plastic deformation in the middle crust may be small. However, grain growth might become important for deformation in the lower crust when the strain rate is < 10−12 s−1.

scholarly journals The Effect of Hydrogen on Martensite Transformations and the State of Hydrogen Atoms in Binary TiNi-Based Alloy with Different Grain Sizes

Materials ◽  
2019 ◽  
Vol 12 (23) ◽  
pp. 3956 ◽  
Author(s):  
Baturin ◽  
Lotkov ◽  
Grishkov ◽  
Rodionov ◽  
Kabdylkakov ◽  
...  
Keyword(s):  
Grain Size ◽  
Surface Layer ◽  
Room Temperature ◽  
Hydrogen Diffusion ◽  
Thermal Desorption Spectroscopy ◽  
Coarse Grained ◽  
Hydrogen Atoms ◽  
Grain Sizes ◽  
Martensite Transformations ◽  
Kinetics Of

The analysis presented here shows that in B2-phase of Ti49.1Ni50.9 (at%) alloy, hydrogenation with further aging at room temperature decreases the temperatures of martensite transformations and then causes their suppression, due to hydrogen diffusion from the surface layer of specimens deep into its bulk. When hydrogen is charged, it first suppresses the transformations B2↔B19′ and R↔B19′ in the surface layer, and when its distribution over the volume becomes uniform, such transformations are suppressed throughout the material. The kinetics of hydrogen redistribution is determined by the hydrogen diffusion coefficient DH, which depends on the grain size. In nanocrystalline Ti49.1Ni50.9 (at%) specimens, DH is three times greater than its value in coarse-grained ones, which is likely due to the larger free volume and larger contribution of hydrogen diffusion along grain boundaries in the nanocrystalline material. According to thermal desorption spectroscopy, two states of hydrogen atoms with low and high activation energies of desorption exist in freshly hydrogenated Ti49.1Ni50.9 (at%) alloy irrespective of the grain size. On aging at room temperature, the low-energy states disappear entirely. Estimates by the Kissinger method are presented for the binding energy of hydrogen in the two states, and the nature of these states in binary hydrogenated TiNi-based alloys is discussed.

Texture Evolution during Grain Growth under the Influence of Mechanical Stresses

2005 ◽  
Vol 495-497 ◽  
pp. 1279-1284 ◽  
Author(s):  
Myrjam Winning
Keyword(s):  
Grain Size ◽  
Grain Growth ◽  
Texture Evolution ◽  
Mechanical Stresses ◽  
Stress Fields ◽  
Grain Sizes ◽  
Purity Aluminium ◽  
High Purity Aluminium ◽  
Kinetics Of ◽  
Growth Experiments

In order to study the influence of mechanical stress fields on the kinetics and texture evolution of grain growth, experiments were performed on high purity aluminium. Samples were annealed under the influence of different mechanical stresses. The temporal evolutions of grain sizes and of macrotexture were analysed in ependence on the applied stress. The results show that mechanical stresses can change the kinetics of grain growth and slow down the increase in the grain size. Also effects on the texture evolution were observed and shall be discussed.

Elastic Modulus of Pb/Sn Solder Joints in Microelectronics

2002 ◽  
Author(s):  
Cemal Basaran ◽  
Jianbin Jiang
Keyword(s):  
Grain Size ◽  
Elastic Modulus ◽  
Single Crystal ◽  
Solder Alloy ◽  
Ultrasonic Testing ◽  
Heterogeneous Materials ◽  
Testing Methods ◽  
Nano Indentation ◽  
Deformation Kinetics ◽  
Kinetics Of

Young’s modulus (E) values published in literature for the eutectic Pb37/Sn63 and near eutectic Pb40/Sn60 solder alloy vary significantly. One reason for this discrepancy is different testing methods for highly rate sensitive heterogeneous materials, like Pb/Sn alloys, yield different results. In this paper, we study different procedures used to obtain the elastic modulus; analytically, by single crystal elasticity and experimentally by ultrasonic testing and Nano indentation. We compare these procedures and propose a procedure for elastic modulus determination. The deformation kinetics of the Pb/Sn solder alloys is discussed at the grain size level.

Crystal-growth kinetics of protein single crystals along capillary tubes in the gel-acupuncture technique

1999 ◽  
Vol 55 (2) ◽  
pp. 577-580 ◽  
Author(s):  
Abel Moreno ◽  
Manuel Soriano-García
Keyword(s):  
Growth Rate ◽  
Crystal Growth ◽  
Capillary Tube ◽  
Crystal Growth Rate ◽  
Equilibrium Studies ◽  
Acta Cryst ◽  
Average Growth ◽  
X Ray Crystallography ◽  
Growing Cell ◽  
Kinetics Of

In attempts to obtain protein crystals of a sufficient size for structural studies, lack of knowledge of the physicochemical properties of protein solutions and of their crystal-growth behaviour lead to a bottleneck for drug design as well as for X-ray crystallography. Most formal investigations on crystal-growth phenomena have been focused on equilibrium studies, where the protein is soluble, and on the kinetics of crystal growth, which is related to both nucleation and crystal-growth phenomena. The aim of this work is to measure the crystal-growth rate along a capillary tube used as a growing cell. These experiments were carried out using the gel-acupuncture technique [García-Ruiz et al. (1993). Mater. Res. Bull. 28, 541–546; García-Ruiz & Moreno (1994). Acta Cryst. D50, 484–490; García-Ruiz & Moreno (1997). J. Cryst. Growth, 178, 393–401]. Crystal-growth investigations took place using lysozyme and thaumatin I as standard proteins. The maximum average growth rate obtained in the lower part of the capillary tube was about 35 Å s−1 and the minimum average growing rate in the upper part of the capillary tube was about 8 Å s−1. The crystal-growth rate as a function of the supersaturation was experimentally estimated at a constant height along the capillary tube.

scholarly journals Investigation of Movement of Nourishment Sand of Different Grain Sizes Using Model for Predicting Bathymetric and Grain Size Changes

2009 ◽  
Vol 65 (1) ◽  
pp. 691-695
Author(s):  
Yasuhito NOSHI ◽  
Akio KOBAYASHI ◽  
Takaaki UDA ◽  
Masumi SERIZAWA ◽  
Takayuki KUMADA
Keyword(s):  
Grain Size ◽  
Grain Sizes
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