Flashcards
Material Science Test 3 Flashcards
Cards in this deck (20)
- 1Dislocations1-D defects
Atoms are misaligned - 2Edge dislocationb perpendicular to dislocation line
Extra half plane of atoms inserted in a crystal structure
Can be caused by added shear stress
Atom bonds are broken or reformed along slip plane - 3Screw dislocationb parallel to dislocation line
Spiral planar ramp resulting from shear deformation - 4SlipProcess where plastic deformation occurs by motion of dislocations
Occurs at slip plane - 5Metal dislocation characteristicsDislocation motion is easy
Metallic bonding is non-directional
Planes and directions for slip are closely packed
ex.) copper, aluminum, iron - 6Ceramic dislocation characteristics (covalent)Dislocation motion is difficult
Covalent bonding is directional
ex.) silicon, diamond - 7Ceramic dislocation characteristics (ionic)Dislocation motion is difficult
Few slip systems
eg.) NaCl, MgO - 8Slip systemCombination of a slip plane and slip direction
- 9Slip planeHigh planar density
Plane where slip happens most easily - 10Slip directionDirection with high linear density
Direction along which slip happens most easily - 11Tensile stress TR relationshipTR=(sigma)cos(lamda)cos(phi)
sigma=F/A - 12Methods for strengthening metalsGrain size reduction
Solid solution strengthening
Strain hardening (cold working) - 13Grain size reductionGrain boundaries act as barriers to dislocation motion
At boundary: slip planes change direction (discontinuity)
Reducing grain size increases grain boundary area, increases amount of barriers, and increases yield strength, tensile strength, and hardness - 14yield sigma and average grain diameter relationshipsigma yield=sigma0+kyd^-1/2
- 15Solid solution strengtheningLattice strains around dislocations
Compression/tension
Tensile and yield strength increase with wt% Ni - 16Percent cold work equation%CW=((A0-Ad)/A0)*100
- 17Phase diagramsTop: liquid
Middle: liquid + alpha
Bottom: alpha - 18What can we determine from phase diagrams?Which phase something is (tie line=line that connects L and alpha in L+alpha phase)
Weight fraction - 19Weight fraction equationWL=S/(R+S)
S=distance of tie line from point to alpha
R=distance of tie line from point to L
Walpha=R/(R+S)
WL and Walpha should add to 1 - 20—
Information
- Description
- Engineering Flashcards on Material Science Test 3 Flashcards, created by Anna Grunkemeyer on 12/11/2024.
- Created by
- Anna Grunkemeyer
- Views
- 1
- Rating