Concept explainers
The value for the activation energy for viscous flow.
Answer to Problem 104AAP
The value for the activation energy for viscous flow is
Explanation of Solution
Write the equation involving the viscosity to temperature for a viscous flow in the glass.
Here, viscosity of the glass is
For the annealing point, write the equation involving the viscosity to temperature for a viscous flow in the glass.
Here, viscosity of the glass at strain point is
For the softening point, write the equation involving the viscosity to temperature for a viscous flow in the glass.
Here, viscosity of the glass at softening point is
Conclusion:
Convert the unit of annealing point temperature to absolute value.
Convert the unit of softening point temperature to absolute value.
Divide Equation (II) by Equation (III).
Substitute
Thus, the value for the activation energy for viscous flow is
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Chapter 11 Solutions
Foundations of Materials Science and Engineering
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