Calculation of the Activation Energy for Super Plastic Flow in Zn-22Al Alloy

The essential objective of this work is to establish the influence of grain size and thermo-mechanical conditions on the activation energy for super plastic flow (QSPF) in Ti-6Al-4V alloy by applying the quantum mechanics and relativistic model (QM-RM) proposed by Muñoz-Andrade, in the framework of the unified physics. The QM-RM allows the direct determination of the QSPF in advanced materials at instantaneous thermo-mechanical material working conditions. By applying, the QM-RM on the experimental results reported previously by some authors, it is shown for grain size of 6.1μm, that the calculated QSPF for grain boundary sliding is about 193 and 178 kJ/mol, at 850°C with an efficiency of power dissipation, η=0.65. These results are in closed agreement with the values of 204 and 174 kJ/mol reported previously for grain boundary self-diffusion energy of α-Ti. Nevertheless, for grain size of 0.6μm the calculated QSPF is 142 kJ/mol at 650°C, with an efficiency of power dissipation, η=0.61. As well, in order to understand the phenomenology and mechanics of SPF in Ti-6Al-4V alloy, the variation of the activation energy with the temperature; stress and strain rate is analyzed in association with coupled mechanisms during SPF, such as grain boundary sliding, cooperative grain boundary sliding and self-accommodation process related to the microstructure. In summary, the results of QSPF obtained in this work, by the QM-RM are in closed agreement with results reported previously by using the theoretical and conventional methodology set up by Mohamed and Langdon.

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Unification of Physics during Super Plastic Flow in Advanced Materials

Materials Science Forum ◽

10.4028/www.scientific.net/msf.838-839.78 ◽

2016 ◽

Vol 838-839 ◽

pp. 78-83 ◽

Cited By ~ 1

Author(s):

Juan Daniel Muñoz-Andrade

Keyword(s):

Activation Energy ◽

Grain Boundary ◽

Plastic Flow ◽

Grain Boundary Sliding ◽

Dislocation Dynamics ◽

Advanced Materials ◽

Direct Evaluation ◽

Super Plastic ◽

Boundary Sliding ◽

Material Forming

In the framework connected with the unification of physics, the activation energy for super plastic flow in advanced materials has been obtained by applying the new quantum mechanics and relativistic model proposed by Muñoz-Andrade. This new model allows the direct evaluation of the activation energy for super plastic flow at instantaneous thermo-mechanical material forming conditions. Also, in order to establish the phenomenology and mechanics of super plastic flow, the dependence on strain rate and phase velocity de Broglie is obtained, for the reason that the nature wavelength of the cellular dislocations is essential in the association with coupled mechanisms during super plastic flow, such as grain boundary sliding, cooperative grain boundary sliding and self-accommodation process. In conclusion, cellular dislocation dynamics is a nature mechanism during super plastic flow in advanced materials. The results obtained in this work are in a closed agreement with results reported previously.

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Mathematical Model for Super Plastic Flow in Advanced Structural Materials

Materials Science Forum ◽

10.4028/www.scientific.net/msf.551-552.67 ◽

2007 ◽

Vol 551-552 ◽

pp. 67-72

Author(s):

Juan Daniel Muñoz-Andrade

Keyword(s):

Activation Energy ◽

Mathematical Model ◽

Plastic Flow ◽

Planck Scale ◽

Mathematical Expression ◽

Frequency Factor ◽

Structural Materials ◽

Strong Temperature Dependence ◽

Super Plastic ◽

The Universe

Everything in the universe is a result of their own evolution, in consequence all advanced structural materials are physical objects spatially extended in a permanently cosmic connection with the advanced structural universe. In this context, the nature expansion rate of the universe (ξ u) was obtained in a similar way of super plastic flow in terms of the rate reaction theory, with the strong temperature dependence of strain rate as follow: exp 70( / sec)/ 2.26854593 . 18 1 0 − − = =         −         = = km Mpc s kT c Q H P P P u λ ξ Where, QP = the Planck activation energy of the system at the Planck scale (QP = 1.221x1028eV), λP = Planck length (λP = 1.62x10-35m), c = the speed of light (c = 299 792 458 m/s), (c/λP) = the overall frequency factor, k = the Boltzmann constant (k = 8.617x10-5eV/K), TP = the Planck temperature (TP = 1.010285625x1030K) and H0 = the Hubble constant. On the basis of this mathematical expression and their combination with the Orowan equation, it was obtained the mathematical model to predict the activation energy (Q) that is necessary to the glide cellular dislocations during deformation of the super plastic advanced structural materials. Consequently, in this work the application of this mathematical model for super plastic flow in advanced structural materials and the concept of cellular dislocation are reviewed in order to integrate in a general form the unified interpretation of Hubble flow, plastic flow and super plastic flow [1-3].

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On the activation energy for plastic flow during tension test at room temperature and the anisotropy behaviour of Ti-6Al-4V alloy

Journal of Physics Conference Series ◽

10.1088/1742-6596/1723/1/012046 ◽

2021 ◽

Vol 1723 (1) ◽

pp. 012046

Author(s):

J D Muñoz-Andrade ◽

M Aguilar-Sánchez

Keyword(s):

Activation Energy ◽

Plastic Flow ◽

Room Temperature ◽

Tension Test

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PLASTIC DEFORMATION OF THICK-WALLED SNOW-ICE CYLINDERS UNDER HYDROSTATIC PRESSURE

Canadian Journal of Physics ◽

10.1139/p62-139 ◽

1962 ◽

Vol 40 (10) ◽

pp. 1310-1318 ◽

Cited By ~ 1

Author(s):

H. H. G. Jellinek

Keyword(s):

Activation Energy ◽

Plastic Deformation ◽

Hydrostatic Pressure ◽

Strain Rate ◽

Plastic Flow ◽

Constant Pressure ◽

Circumferential Stress ◽

Sine Function ◽

Kcal Mole ◽

Flow Process

The results of experiments on the plastic deformation of hollow snow-ice cylinders, closed at one end, as a function of circumferential stress and temperature are discussed. Data are graphed on deformation as a function of time for a snow-ice cylinder under 7.03 and 14.06 kg/cm2 hydrostatic pressure at −4.5 °C, deformation as a function of hydrostatic pressure from 2.11 to 7.03 kg/cm2, and deformation as a function of temperature at a constant pressure of 10.55 kg/cm2. The natural strain rate of closure at constant circumferential stress and temperature was a constant, which varied with circumferential stress as a sine function and was "exponentially dependent on temperature, with an activation energy of 14.1 kcal/mole at an average circumferential stress of 3.1 kg/cm2. The experiments agree well with an earlier interpretation of the plastic flow process representing flow between grain boundaries.

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