unit 1

Question 1

what are the two types of material failure?

Answer 1

Deformation, Fracture

Question 2

what are the two types of deformation

Answer 2

Time independant: elastic and plastic

Time dependant:
Creep

Question 3

what are the two types of Fracture failure

Answer 3

Static Loading:
-brittle
-ductile
-environmental
-creep rupture

Fatigue Cyclic Loading:
-High Cycle
-Low Cycle
-Fatigue Crack Growth
-Corrosion Fatigue

Question 4

What’s Deformation Failure

Answer 4

when the physical dimensions of the sample change.

Elastic deformation recovers

Plastic deformation is permanent

Question 5

What is fracture?

Answer 5

formation of cracks in the material

Question 6

What is corrosion?

Answer 6

loss of material due to chemical action

Question 7

What is creep?

Answer 7

accumulation of deformation with time under sustained loading

Question 8

What is fatigue failure?

Answer 8

high-cycle fatigue, caused by relatively large number (+1,000,000) of load cycles

Low-cycle fatigue: caused by a relatively small number of load cycles

Question 9

What is Safety Factor?

Answer 9

ratio between (stress causing failure)/(stress in service)

ratio between (failure life)/(desired service life)