Calculate the number of vacancies per cubic meter

MET180 – Structure and Properties of Materials

TAP 3 F2

Date: Section:

Name: ID:

Question 1: Application of Hume–Rothery rules (32 Pts, each 8 pts)

By checking the Hume- Rothery rules determine the given solids form:

· COMPLETE SUBSTITUTIONAL SOLID SOLUTION

· INCOMPLETE SUBSTITUTIONAL SOLID SOLUTION

· INTERSTITIAL SOLID SOLUTION

Please show your steps while you are following the rules and your answer should be as given the example below:

( ie: Zn meeting the Rule 1, 2 and 4 but not the Rule 3: Incomplete Substitutional Solid Solution with Cu )

(Type your answers using blue color)

a) Ni and Pd:

b) Ni and Zn:

c) Ni and Ag:

d) Ni and C:

Question 2: Chemical Protective Clothing (CPC) (28 Pts, each 14 pts)

Methylene chloride is a common ingredient of paint removers. Besides being an irritant, it also may be absorbed through skin. When using this paint remover, protective gloves should be worn.

a) If butyl rubber gloves (0.058cm thick) are used, what is the diffusive flux (J) of methylene chloride through the glove?

b) What is the breakthrough time (tb), i.e., how long could the gloves be used before methylene chloride reaches the hand?

Data:

– diffusion coefficient in butyl rubber: D = 124x10-8 cm2/s

– surface concentrations: C1 = 0.56 g/cm3 and C2 = 0.04 g/cm3

Note: Assume linear concentration gradient, l = x2 - x1 = thickness of the glove

Question 3: Diffusion Simulation (40 Pts, each 8 pts)

· By using excel create a random diffusion simulation. Please follow the video link given to get the instructions step by step.

· Important note: By using rand() function, each student will have different numbers and charts.

· Follow the instructions in the video and continue for 5 steps in total.

· After generating the graphs adjust the scale according to your numbers to show the motion better.

· Insert all those 5 graphs here, including the time=0 .

· Submit your excel file with the assignment.

· Name all your files as TAP3_yourID.

Diffusion simulations in excel: https://www.youtube.com/watch?v=xF16hrCJwJ4

Insert your graphs here with the correct sequence to show the diffusion progress at each step:

Question 4: (Bonus: 10 Pts)

Calculate the number of vacancies per cubic meter in iron at 945 °C. The energy for vacancy formation is 1.12 eV/atom. Furthermore, the density and atomic weight for Fe are 7.65 g/cm and 55.85 g/mol, respectively.