CHAPTER 12 Flashcards
(5 cards)
1
Q
How does r_cat/r_anion relate to the coordination number?
A
coordination number increases with r_cat/r_anion
1
Q
When is bond hybridization possible?
A
When there is significant covalent bonding so hybrid electron orbitals form
2
Q
What are the types of point defects in ceramics?
A
-Vacancies (of both anion or cations)
-Interstitials (where theyre not supposed to be) for cations
-Frenkel defect (cation displaced)
-Shottky defect (vacancies of pair)
3
Q
What is the important rule when it comes to imperfections
A
Electroneutrality must be maintained
4
Q
Why are ceramic materials more brittle than metals?
A
Ceramics are highly ionic…so dislocation motion is difficult
-few slip systems
-resistance to motions of ions of like charge past one another
