Concept explainers
(a)
The total stage II creep strain theory for the alloy.
(a)
Answer to Problem 9.5P
The total stage II creep strain theory for the alloy at
Explanation of Solution
Given:
The tensile stress of super alloy is
The creep-rate equation is
Formula Used:
Write the expression for the total stage II creep strain as:
Here,
Calculation:
Substitute
Conclusion:
Thus, the total stage II creep strain theory for the alloy at
(b)
The stage II creep rate of the alloy at
(b)
Answer to Problem 9.5P
The stage II creep rate of the alloy at
Explanation of Solution
Given:
The tensile stress of super alloy is
The creep-rate equation is
Formula Used:
Write the expression for the tensile stage II creep strain.
Here,
Write the expression for the ratio of strain rates of
Here,
Calculation:
Substitute
Conclusion:
Thus, the stage II creep rate of the alloy at
(c)
The activation enthalpy for creep in
(c)
Answer to Problem 9.5P
The activation enthalpy for creep in
Explanation of Solution
Formula Used:
Write the expression for the ratio of strain rates of
Here,
Calculation:
Substitute
Take log both side,
Conclusion:
Thus, the activation enthalpy for creep in
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Chapter 9 Solutions
Materials Science And Engineering Properties
- An aluminium specimen with an initial gauge diameter d, = 10 mm and gauge length, 1, = 100 mm is %3D subjected to tension test. A tensile force P= 50 kN is applied at the ends of the specimen as shown, resulting in an elongation of 1 mm in gauge length. The Poisson's ratio (µ) of the specimen is Take shear modulus of material, G = 25 GPa. Consider engineering stress-strain conditions. Parrow_forwardA plate in equilibrium is subjected to uniform stresses along its edges with magnitude o = 30 %3D MPa and ow = 50 MPa as shown in the figure. %3D = 50 MPa %3D O = 30 MPa XX ple The Young's modulus of the material is 2 x 1011 N/m2 and the Poisson's ratio is 0.3. If o is negligibly small and assumed to be zero, then the strain Ezz isarrow_forwardTwo triangular wedges are glued together as shown in the figure. The stress acting normal to the interface, o, is MPa. 100 MPa 100 MPa on 45% 100 MPa -100 MPaarrow_forward
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- Example: the low cycle fatigue of a certain steel is given by life cycle equation-2: (of/E)=0.005 E=0.07 b= -0.08 c= -0,7 a. What is the value of the transition fatigue life, in this case 2 N/when E - Ep b. What is the total strain amplitude at the transition fatigue life?arrow_forwardExample: the low cycle fatigue of a certain steel is given by life cycle equation-2: (ay/E)=0.005 -0.07 b= -0.08 c= -0.7 a. What is the value of the transition fatigue life, in this case 2 N/when EE - Ep b. What is the total strain amplitude at the transition fatigue life?arrow_forwardQ.3. (30%) A circular aluminum tube subjected to T pure torsion by torques T has an outer radius r2 equal to 2 times the inner radius r1. (a) If the maximum shear strain in the tube is measured as 500x10-6 rad, what is the shear strain y1 at the inner surface? (b) If the maximum allowable rate of twist (0) is 0.15°/m and the maximum shear strain is to be kept at 500x10-6 rad by adjusting the torque T, what is the minimum required outer radius (r2 )min?arrow_forward
- Materials Science And Engineering PropertiesCivil EngineeringISBN:9781111988609Author:Charles GilmorePublisher:Cengage Learning