30-05-2012, 04:24 PM
Material Science
Ma t e r i a l S c i e n c e.pdf (Size: 655.97 KB / Downloads: 108)
Diffusion
Mass Transfer (Atomic) e.g. Migration
Mechanisms
- In Gases & Liquids via Brownian Motion
- In Solids via Vacancy or Interstitial Diffusion
Diffusion in Solids
- Condition: Empty Sites, Atomic Size, Energy
- Extent: Vibrational Magnitude, Temperature
Diffusion in Metals
- Vacancy: High temp, Position exchanges
- Interstial: Smaller atoms (H,C,N and O)
Importance
- Purification of gases - Case Hardening
- IC Chips Fabrication