Hardness testing - localized deformation Brinell Vickers Knoop Rockwell Hardness/tensile strength...
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![Page 1: Hardness testing - localized deformation Brinell Vickers Knoop Rockwell Hardness/tensile strength correlation Impact testing - energy absorbed upon fracture.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf821a28abf838c85f68/html5/thumbnails/1.jpg)
Hardness testing - localized deformationBrinellVickersKnoopRockwell
Hardness/tensile strength correlation
Impact testing - energy absorbed upon fractureEffect of temperature
Hardness testing - localized deformationBrinellVickersKnoopRockwell
Hardness/tensile strength correlation
Impact testing - energy absorbed upon fractureEffect of temperature
Last classLast class
![Page 2: Hardness testing - localized deformation Brinell Vickers Knoop Rockwell Hardness/tensile strength correlation Impact testing - energy absorbed upon fracture.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf821a28abf838c85f68/html5/thumbnails/2.jpg)
More mechanical testingFracture toughnessFracture surfacesCreepFatigue
Crystal structure
More mechanical testingFracture toughnessFracture surfacesCreepFatigue
Crystal structure
TodayToday
![Page 3: Hardness testing - localized deformation Brinell Vickers Knoop Rockwell Hardness/tensile strength correlation Impact testing - energy absorbed upon fracture.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf821a28abf838c85f68/html5/thumbnails/3.jpg)
Fracture toughness - KIc = Yc a
resistance to brittle fracture in presence of
a crack - resistance to crack propagationunder load
Fracture toughness - KIc = Yc a
resistance to brittle fracture in presence of
a crack - resistance to crack propagationunder load
Common specimen configurations
pre-cracked here before testing - usually 1000 cycles, 0.03 in/in strain
Common specimen configurations
pre-cracked here before testing - usually 1000 cycles, 0.03 in/in strain
![Page 4: Hardness testing - localized deformation Brinell Vickers Knoop Rockwell Hardness/tensile strength correlation Impact testing - energy absorbed upon fracture.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf821a28abf838c85f68/html5/thumbnails/4.jpg)
Fracture toughness
Hypothetical example - surface crack in a semi-infinite sheet loaded in tension
Find critical crack size
Fracture toughness
Hypothetical example - surface crack in a semi-infinite sheet loaded in tension
Find critical crack size
![Page 5: Hardness testing - localized deformation Brinell Vickers Knoop Rockwell Hardness/tensile strength correlation Impact testing - energy absorbed upon fracture.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf821a28abf838c85f68/html5/thumbnails/5.jpg)
Some fracture surfacesSome fracture surfaces
ductile fractureductile fracture
transgranularfracture
transgranularfracture
intergranularfracture
intergranularfracture
![Page 6: Hardness testing - localized deformation Brinell Vickers Knoop Rockwell Hardness/tensile strength correlation Impact testing - energy absorbed upon fracture.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf821a28abf838c85f68/html5/thumbnails/6.jpg)
Crack originsCrack origins
![Page 7: Hardness testing - localized deformation Brinell Vickers Knoop Rockwell Hardness/tensile strength correlation Impact testing - energy absorbed upon fracture.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf821a28abf838c85f68/html5/thumbnails/7.jpg)
Creep
deformation under small loads atelevated temps.
Creep
deformation under small loads atelevated temps.
![Page 8: Hardness testing - localized deformation Brinell Vickers Knoop Rockwell Hardness/tensile strength correlation Impact testing - energy absorbed upon fracture.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf821a28abf838c85f68/html5/thumbnails/8.jpg)
Fatigue
deformation under small cyclic loads
Fatigue
deformation under small cyclic loads
![Page 9: Hardness testing - localized deformation Brinell Vickers Knoop Rockwell Hardness/tensile strength correlation Impact testing - energy absorbed upon fracture.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf821a28abf838c85f68/html5/thumbnails/9.jpg)
Fatigue
S-N curves & endurance limit
Fatigue
S-N curves & endurance limit
![Page 10: Hardness testing - localized deformation Brinell Vickers Knoop Rockwell Hardness/tensile strength correlation Impact testing - energy absorbed upon fracture.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf821a28abf838c85f68/html5/thumbnails/10.jpg)
Fatigue failure
fatigue crack w/ beachmarks
Fatigue failure
fatigue crack w/ beachmarks
![Page 11: Hardness testing - localized deformation Brinell Vickers Knoop Rockwell Hardness/tensile strength correlation Impact testing - energy absorbed upon fracture.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf821a28abf838c85f68/html5/thumbnails/11.jpg)
Crystal structures of materials - where are the atoms?
Polymers - mostly not crystallinestructure extremely complicated
Ceramic materials - complicatedmany different types of atom arrangements
Crystal structures of materials - where are the atoms?
Polymers - mostly not crystallinestructure extremely complicated
Ceramic materials - complicatedmany different types of atom arrangements
Metals - really simple - most have one of three typesMetals - really simple - most have one of three types
![Page 12: Hardness testing - localized deformation Brinell Vickers Knoop Rockwell Hardness/tensile strength correlation Impact testing - energy absorbed upon fracture.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf821a28abf838c85f68/html5/thumbnails/12.jpg)
Crystal structures of pure metalsCrystal structures of pure metals
Most pure metals exhibit one of three types
1. cubic close packing (ccp or A1)2. hexagonal close packing (hcp or A3)3. A2 (almost universally referred to by
the confusing notation 'bcc')
Most pure metals exhibit one of three types
1. cubic close packing (ccp or A1)2. hexagonal close packing (hcp or A3)3. A2 (almost universally referred to by
the confusing notation 'bcc')
![Page 13: Hardness testing - localized deformation Brinell Vickers Knoop Rockwell Hardness/tensile strength correlation Impact testing - energy absorbed upon fracture.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf821a28abf838c85f68/html5/thumbnails/13.jpg)
Crystal structures of pure metals
cubic close-packed (ccp)
close-packed plane of atoms
Crystal structures of pure metals
cubic close-packed (ccp)
close-packed plane of atoms
![Page 14: Hardness testing - localized deformation Brinell Vickers Knoop Rockwell Hardness/tensile strength correlation Impact testing - energy absorbed upon fracture.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf821a28abf838c85f68/html5/thumbnails/14.jpg)
Crystal structures of pure metals
cubic close-packed (ccp)
ABCABC layer sequence close-packed plane of atoms
Crystal structures of pure metals
cubic close-packed (ccp)
ABCABC layer sequence close-packed plane of atoms
AB
C
A
AB
C
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Crystal structures of pure metals
hexagonal close-packed (hcp)
Crystal structures of pure metals
hexagonal close-packed (hcp)
Zn, Cd, Co, Ti, Zr……Zn, Cd, Co, Ti, Zr……
close-packed plane of atoms
hexagonhexagon
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Crystal structures of pure metals
hexagonal close-packed (hcp)
ABAB layer sequence close-packed plane of atoms
Crystal structures of pure metals
hexagonal close-packed (hcp)
ABAB layer sequence close-packed plane of atoms
AB
AB
AB
![Page 17: Hardness testing - localized deformation Brinell Vickers Knoop Rockwell Hardness/tensile strength correlation Impact testing - energy absorbed upon fracture.](https://reader035.fdocuments.us/reader035/viewer/2022062217/5697bf821a28abf838c85f68/html5/thumbnails/17.jpg)
Fe, V, Cr, Mo, W, Ta……Fe, V, Cr, Mo, W, Ta……
Crystal structures of pure metals
A2 structure - so-called "bcc" metal structure
almost close-packed atom planes
Crystal structures of pure metals
A2 structure - so-called "bcc" metal structure
almost close-packed atom planes
some empty space some empty space