1 / 13

3.14/3.40J/22.71J Recap Basic Crystallography and Miller Indices

3.14/3.40J/22.71J Recap Basic Crystallography and Miller Indices. Ting-Yun Huang 2012 Sep. 18 th. Outline. Basic Structures Cubic: FCC/BCC HCP Miller Indices From 3D to 4D: Miller indices for hexagonal crystals From 3D to 2D: Stereographic Projection Zone axis. BCC/FCC /HCP.

kenton
Download Presentation

3.14/3.40J/22.71J Recap Basic Crystallography and Miller Indices

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. 3.14/3.40J/22.71J RecapBasic Crystallography and Miller Indices Ting-Yun Huang 2012 Sep. 18th

  2. Outline • Basic Structures • Cubic: FCC/BCC • HCP • Miller Indices • From 3D to 4D: Miller indices for hexagonal crystals • From 3D to 2D: Stereographic Projection • Zone axis

  3. BCC/FCC /HCP BASIC STRUCTURES

  4. Basic Structures: BCC • Coordination number = 8 • Number of atoms in unit cell = 2 • α-Fe(room temperature) , δ-Fe(high T), β-Ti(high T), Zr (high T)

  5. Basic Structures: FCC • Coordination number = 12 • Number of atoms in unit cell = 4 • Closest packing • ABCABC packing • γ-Fe, Cu, Ag, Au, Al, Ni, Pb, Pt

  6. Basic Structures: HCP • Coordination number = 12 • Number of atoms in unit cell = 2(*) • Closest packing • ABAB packing • Mg, Zn, α-Ti, Be, Cd, Zr (low T)

  7. Notations/Hexagonal Systems/Stereographic Projection MILLER INDICES

  8. Miller Indices-Notations • Directions • Specific Direction: [u1 u2 u3] • Family of Directions: <u1 u2 u3> • Planes • Reciprocal of the intercepts • Specific Plane: (u1 u2 u3) • Family of Planes: {u1 u2 u3}

  9. From 3D to 4D-Miller indices for HCP structures • Constraints: • [u1u2u3v]→u1a1+u2a2+u3a3+vc • u1+u2+u3 = 0 • Redundant coordinate system which is not orthogonal • But we can still perform inner product.

  10. From 3D to 2D-Stereographic Projection

  11. Zone axis In this TEM diffraction, the structure is FCC and the zone axis is [112]. The (11-1) and (2-20) plane have the same zone axis [112]. _ (111) _ (220)

  12. From 3D to 2D-Stereographic Projection

  13. Thank you!

More Related