Reference no: EM131216403
Mechanical Behavior of Materials Assignment-
Q1. Using the figure on the right, perform the following
a) Obtain approximate values of fracture toughness KIc and yield strength σo for A533B steel at temperatures of - 150oC and +10oC.
b) For each temperature, make a plot of stress versus crack length, showing the yielding line alone, and the fracture alone curve (similar to Figure 8.6 in the book, slide 20 in the notes).
c) Compare the two plots and comment on the engineering use of this steel at these two temperatures.
Q2. Consider a center-cracked plate in tension with the accurate values of F given in the table
a) Compare these values with the expression for F that is recommended for any α. What is its accuracy for α ≤ 0.9?
b) Two expressions that are sometimes used for F that are employed for center-cracked plates are
F = √(sec(πα/2)), F = √((2/απ)tan(πα/2)) (b, c)
Compare each of these with the numerical values, and characterize the accuracy of each for α ≤ 0.9
|
α = a/b
|
0
|
0.1
|
0.2
|
0.3
|
0.4
|
0.5
|
0.6
|
0.7
|
0.8
|
0.9
|
|
F = F(α)
|
1.000
|
1.006
|
1.025
|
1.058
|
1.109
|
1.187
|
1.303
|
1.488
|
1.816
|
2.578
|
Q3. A cylindrical pressure vessel has an inner diameter of 25 cm and wall thickness of 20 mm, contains a pressure of 50 MPa. The safety factor against yielding must be at least Xo = 3. Also a leak-before-break criterion must be met with a safety factor of Xa = 5 on crack length, requiring cc ≥ Xat
- Choose an appropriate material that can satisfy the leak-before-break condition and meets the safety factor in yielding (Use von-Mises theory)
Q4. AISI 4142 steel tempered at 205oC, used for airplane landing gears, has a Gc value of 10000 N/m. A nondestructive examination technique capable of detecting cracks that are 1 mm long is available.
Compute the stress level that the landing gear can support without failure. Assume the situation to be a single edge cracked member with relatively large width and height. Use units of K as MPa√m.
|
Explain tay-sachs disease
: Explain Tay-Sachs disease. Imagine you are a genetic counselor working with a couple who have just had a child who is suffering from Tay-Sachs disease. Neither parent has been tested for Tay-Sachs disease nor have there been any previous cases of ..
|
|
Discuss rational decision making model
: Discuss that decision in terms of the rational decision making model. How could you have improved your decision?
|
|
Identify the main characters dramatic need
: Referring back to your favorite film, identify the dramatic premise (that which provides the initial dramatic thrust and leads us into the story). Identify the main characters dramatic need (what he or she wants to win, gain, or achieve during th..
|
|
Wide sense stationary random process
: Let X (t) be a wide sense stationary random process that is ergodic in mean and the autocorrelation.- Show that Y(t) is not ergodic in the mean or the autocorrelation.
|
|
Obtain approximate values of fracture toughness
: ME 475 Mechanical Behavior of Materials Assignment. Obtain approximate values of fracture toughness KIc and yield strength σo for A533B steel at temperatures of - 150oC and +10oC
|
|
Discuss how bias has blocked your ability
: Discuss how bias has blocked your ability to make a rational decision - In your answer, discuss the heuristic that you may have used and the bias associated with that heuristic.
|
|
Find the mean function and the autocorrelation function
: Let X (t) be a WSS random process with mean and autocorrelation function- Find the mean function oF. - Find the autocorrelation function of.
|
|
Explain the availability and affect heuristics
: Explain the availability, representativeness, and affect heuristics. In your answer, compare the three and discuss the positive and negative aspects of each.
|
|
Plot the vertical total and effective stresses and pore-wat
: A soil section, as shown in Figure P7.18, has a perched groundwater level. Plot the vertical total and effective stresses and pore-water pressures with depth along sections A-A and B-B. Neglect pore air pressure.
|