Lecture Problem 17

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Lecture Problem 17

• Michael Dayringer

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Problem Statement

• 17a. Identify the following plane

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Answer

• The intercepts are x2, y2, z1
• This yields the plane (1 1 2)

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Problem Statement

• 17b. Calculate the planar packing density (in
  atoms/nm2) of this plane in chromium.
• Properties in Table 3.1, pg. 35 of Callister
• Chromium is BCC with R 0.1249 nm

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Approach

• 1. Find a tessellating plane section
• 2. Count atoms in the section
• 3. Find area of the section
• 4. Calculate PPD

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Answer

• Our plane section contains 4 atoms
• Plane section is a rhombus
• Area 0.407 nm2
• Planar Packing Density 9.82 atoms/nm2