Chapter 5 L12 Flashcards
What is corrosion?
Chemical phenomenon that causes destructive effects to metals
What are the conditions for corrosion to happen?
- 2 dissimilar materials (anode and cathode)
- Electrolyte (Corrosive liquid) (medio)
- Conductor (help flow of electrons)
Explain the electrochemical process in a Galvanic cell
“Notes”
Why is it helpful to group materials based on Galvanic properties?
To determine which one will act as an anode or as a cathode
- Más arriba, más catodic
What is corrosion rate?
Rate of material removal as consequence of corrosion
Name 5 corrosion types
“Notes”
Name essencial sources of corrosion
- Maintainance problems
- Environmental conditions
- Material selection
Do ceramics and polymers exhibit corrosion?
No. They do not corrode, but they experience degradation
Why are optical properties relevant?
It is used to predict and modify material’s response to electromagnetic radiation
What are the 2 main interactions between electromagnetic radiation and atoms/ions/e-?
- Electronic polarization (electric cloud shifted)
- Electron transitions (e- transition to other energy state)
What is the difference between transparency, translucency and opacity?
- Transparency: Light passes through
- Translucency: Some light passes through
- Opacity: No light passes through
How are optical properties defined?
Materials respone to visible light (electromagnetic radiation)
Name the main optical properties of metals and non-metals
- Metals: Reflection and absorbtion
- Non-metals: Refraction
How are colors of materials and wavelength distribiution related?
The color of a material is the wavelength emitted my them
What is magnetism?
The property of attracting or repelling materials
What is a magnetic dipole?
It is the origin of magnetic moments. It has a magnetic north pole and south pole (north → south)
What is a magnetic field vector?
A vector field that describes the magnitude and the direction of the magnetic field
Name essential magnetic parameters.
Relative permeability, permeability and magnetization
Name the different types of magnetism
Diamagnetism, Paramagnetism, Ferromagnetism, Antiferromagnetism
Explain Diamagnetism
No initial magnetic moment
Only appears in presence of an external force (oppsite direction)
Explain Paramagnetism
Initial random permanent magnetic moment
When external force applied, same direction as it
Explain Ferromagnetism
Intial orientated permanent magnetic moment
Present in transition metals
Explain Antiferromagnetism
Initial opposite orientated permanent magnetic moment
Present in ions
