Chapter 4 outline

Question 1

What are the 5 types of crystalline defects?

Answer 1

• point defects
• staking faults
• grain boundaries
• dislocations
• surface defects

Question 2

What is a point defect?

Answer 2

• an imperfection that involved a few atoms at most
• moving atoms away from their equilibrium positions requires an increase in the energy of the system; an increase in strain energy causes an increase in the internal energy of the crystal

Question 3

What is thermodynamically necessary to create a stable crystal?

Answer 3

point defects

Question 4

What are Schottky’s defects?

Answer 4

• a host atom leaves its position in the crystal structure and moves to the surface

Question 5

What kind of atom has Schottky’s and Frankel defects?

Answer 5

ions

Question 6

What are Frankel defects?

Answer 6

defects where a host atom moves into an interstitial position (substitution)

Question 7

Are Frankel defects more common with cations or anions? Why?

Answer 7

cations because they’re smaller than anions and can fit into interstitials easily

Question 8

What is an interstitial solid solution?

Answer 8

a mixture formed when impurities lie in the spaces between solvent atoms

Question 9

What is a substitutional solid solution?

Answer 9

a mixture of 2 species when impurity atoms are substituted for solvent atoms

Question 10

What is an interstitial solid solution?

Answer 10

a mixture formed when impurities lie in the spaces between solvent atoms