LECTURE 2.1LECTURE 2.1

LECTURE OUTLINELECTURE OUTLINE

Weekly DeadlinesWeekly DeadlinesCourse/Lecture PhilosophyCourse/Lecture PhilosophyThe Microscopic Structure of MaterialsThe Microscopic Structure of MaterialsLesson 02 Prototype QuizLesson 02 Prototype Quiz

COURSE PHILOSOPHYCOURSE PHILOSOPHY

To teach scientific literacy by fostering To teach scientific literacy by fostering good (scientific) reading, writing and study good (scientific) reading, writing and study habits.habits.

The primary goal is not to teach materials The primary goal is not to teach materials science and engineering but to use science and engineering but to use principles of materials science to promote principles of materials science to promote scientific literacy.scientific literacy.

LECTURE PHILOSOPHY—OR WHAT LECTURE PHILOSOPHY—OR WHAT PURPOSE IS SERVED BY THE PURPOSE IS SERVED BY THE

LECTURES?LECTURES?

MATSE 081 can be taken either wholly MATSE 081 can be taken either wholly online, or as a blended online/in-class online, or as a blended online/in-class hybrid.hybrid.

For the online group, all of the course For the online group, all of the course content is supplied either online, via videos content is supplied either online, via videos and animations, or by the book.and animations, or by the book.

LECTURE PHILOSOPHY—OR WHAT LECTURE PHILOSOPHY—OR WHAT PURPOSE IS SERVED BY THE PURPOSE IS SERVED BY THE

LECTURES?LECTURES?

If we make the assumption that all content If we make the assumption that all content may be delivered outside the lectures, then may be delivered outside the lectures, then what role should the lectures play?what role should the lectures play?

The lectures should support the The lectures should support the fundamental objective of the course:fundamental objective of the course:To teach scientific literacy by fostering good To teach scientific literacy by fostering good

(scientific) reading, writing and study habits.(scientific) reading, writing and study habits.

LECTURE PHILOSOPHY—OR WHAT LECTURE PHILOSOPHY—OR WHAT PURPOSE IS SERVED BY THE PURPOSE IS SERVED BY THE

LECTURES?LECTURES?

Good reading and study habits are Good reading and study habits are encouraged by the open-book quizzes, and encouraged by the open-book quizzes, and the in-class practice quizzes.the in-class practice quizzes.

Good scientific writing is promoted by the Good scientific writing is promoted by the discussion in class of scientific essay discussion in class of scientific essay components.components.

CLASSIFICATION OF MATERIALS II:CLASSIFICATION OF MATERIALS II:THE (MICROSCOPIC) STRUCTURE OF MATERIALSTHE (MICROSCOPIC) STRUCTURE OF MATERIALS

From the Sublime to the From the Sublime to the Ridiculous!Ridiculous!

THE MICROSCOPESTHE MICROSCOPES

The Light MicroscopeThe Light MicroscopeThe Scanning Electron Microscope (SEM)The Scanning Electron Microscope (SEM)The Transmission Electron Microscope The Transmission Electron Microscope

(TEM)(TEM)The Atomic Force Microscope (AFM)The Atomic Force Microscope (AFM)The Field-Ion Microscope (FIM)The Field-Ion Microscope (FIM)

THE SPACE SHUTTLETHE SPACE SHUTTLE

The skin of the Space Shuttle must withstand The skin of the Space Shuttle must withstand temperatures in excess of 1200˚Ctemperatures in excess of 1200˚C

The “tiles” are made from a silica (SiOThe “tiles” are made from a silica (SiO22) glass) glass Amorphous Ceramic/GlassAmorphous Ceramic/Glass

THE SPACE SHUTTLE TILETHE SPACE SHUTTLE TILE

SEM image of the SEM image of the silica (SiOsilica (SiO22) fibers) fibers Non-MetallicNon-Metallic InorganicInorganic AmorphousAmorphous SyntheticSynthetic CeramicCeramic

Amorphous Ceramic/GlassAmorphous Ceramic/Glass

THE MACROSTRUCTURE OF A THE MACROSTRUCTURE OF A DIAMONDDIAMOND

SEM Image (false color) of a SEM Image (false color) of a small, synthetic diamondsmall, synthetic diamond

The shape of the diamond is The shape of the diamond is an “octahedron”an “octahedron”

Many naturally occurring Many naturally occurring diamonds are also diamonds are also octahedral.octahedral.

Non-MetallicNon-Metallic InorganicInorganic CrystallineCrystalline SyntheticSynthetic Ceramic Ceramic

Crystalline CeramicCrystalline Ceramic

GRAPHITE: AN UNUSUAL GRAPHITE: AN UNUSUAL CERAMICCERAMIC

A Non-Metallic, A Non-Metallic, Elemental SolidElemental Solid

Non-MetallicNon-MetallicInorganicInorganicCrystallineCrystallineNaturalNaturalCeramicCeramic

Crystalline Ceramic:Crystalline Ceramic:Natural CeramicNatural Ceramic

THE ODESSA METEORITETHE ODESSA METEORITE Iron-nickel (~95%fe - 5%ni)Iron-nickel (~95%fe - 5%ni) Scanning electron microscope Scanning electron microscope

(SEM) image(SEM) image Two different polymorphs of Two different polymorphs of

iron: austenite and ferriteiron: austenite and ferrite Note the Note the scale markerscale marker The finger-like mixture of The finger-like mixture of

austenite and ferrite is called austenite and ferrite is called plessiteplessite

MetallicMetallic InorganicInorganic CrystallineCrystalline Naturally OccurringNaturally Occurring MetalMetal

Native Metal/Crystalline MetalNative Metal/Crystalline Metal

SECTIONED ALUMINUM CASTINGSECTIONED ALUMINUM CASTING

The casting solidified or The casting solidified or “crystallized” from the “outside-in”“crystallized” from the “outside-in”

The casting is “polycrystalline”, The casting is “polycrystalline”, The term “polycrystalline” means The term “polycrystalline” means

“consisting of many small, “consisting of many small, differently oriented differently oriented grains, grains, or or crystals”crystals”

MetallicMetallic InorganicInorganic CrystallineCrystalline SyntheticSynthetic MetalMetal

Crystalline MetalCrystalline Metal

BRONZE (COPPER-TIN) BRONZE (COPPER-TIN) POWDERPOWDER

SEM image of SEM image of bronze powderbronze powder

MetallicMetallic InorganicInorganic CrystallineCrystalline SyntheticSynthetic MetalMetal

Crystalline MetalCrystalline Metal

PARTIALLY SINTERED STEELPARTIALLY SINTERED STEEL

Steel: iron with ~ 0.8% Steel: iron with ~ 0.8% carboncarbon

Light micrographLight micrograph The powder particles The powder particles

have begun to sinterhave begun to sinter There is much “residual There is much “residual

porosity”porosity” MetallicMetallic InorganicInorganic CrystallineCrystalline SyntheticSynthetic MetalMetal

Crystalline MetalCrystalline Metal

““DISLOCATIONS” IN DISLOCATIONS” IN ALUMINUMALUMINUM

A “transmission electron A “transmission electron microscope” (TEM) image of microscope” (TEM) image of dislocations in aluminumdislocations in aluminum

Dislocations are “atomic-scale” Dislocations are “atomic-scale” defects that disrupt the crystalline defects that disrupt the crystalline perfection of the aluminumperfection of the aluminum

MetallicMetallic CrystallineCrystalline MetalMetal SyntheticSynthetic MetalMetal

Crystalline MetalCrystalline Metal

IMAGES OF ATOMS IIMAGES OF ATOMS I

Field-ion microscope (FIM) Field-ion microscope (FIM) image of atoms of tungstenimage of atoms of tungsten

Each “bright spot” corresponds Each “bright spot” corresponds to a tungsten atomto a tungsten atom

The atom was first “seen” at The atom was first “seen” at Penn State, in the 1950s, by Penn State, in the 1950s, by professor Irwin Muellerprofessor Irwin Mueller

Note that the tungsten is Note that the tungsten is crystalline.crystalline.

MetallicMetallic InorganicInorganic CrystallineCrystalline SyntheticSynthetic MetalMetal

Crystalline MetalCrystalline Metal

IMAGES OF ATOMS IIIMAGES OF ATOMS II

Atomic force Atomic force microscope (AFM) microscope (AFM) image of gold atomsimage of gold atoms

MetallicMetallic InorganicInorganic CrystallineCrystalline SyntheticSynthetic MetalMetal

Crystalline MetalCrystalline Metal

POLYPROPYLENEPOLYPROPYLENE

Light microscope image of Light microscope image of polypropylenepolypropylene

The thin polymer film was The thin polymer film was crystallized from an initially crystallized from an initially amorphous filmamorphous film

Each “crystal” is seen to Each “crystal” is seen to radiate from a “nucleation site,” radiate from a “nucleation site,” until adjacent crystals impingeuntil adjacent crystals impinge

Non-metallicNon-metallic OrganicOrganic CrystallineCrystalline SyntheticSynthetic PolymerPolymer

200µm

Crystalline PolymerCrystalline Polymer

HIGH DENSITY HIGH DENSITY POLYETHYLENEPOLYETHYLENE

Light microscope image of Light microscope image of “high density polyethylene” “high density polyethylene” (HDPE)(HDPE)

The thin polymer film was The thin polymer film was crystallized from an initially crystallized from an initially amorphous (LDPE) filmamorphous (LDPE) film

Each “crystal” is seen to Each “crystal” is seen to radiate from an “nucleation radiate from an “nucleation site,” until adjacent crystals site,” until adjacent crystals impingeimpinge

Non-MetallicNon-Metallic OrganicOrganic CrystallineCrystalline SyntheticSynthetic PolymerPolymer

Crystalline PolymerCrystalline Polymer

CASHMERECASHMERE

SEM image of a single SEM image of a single thread of cashmerethread of cashmere

Non-MetallicNon-Metallic OrganicOrganic Crystalline (?)Crystalline (?) NaturalNatural PolymerPolymer

Natural Polymer/Crystalline PolymerNatural Polymer/Crystalline Polymer

THE COLUMNS OF STEIDLE THE COLUMNS OF STEIDLE BUILDING IBUILDING I

The columns of Steidle The columns of Steidle Building are constructed Building are constructed from “drums” of sandstonefrom “drums” of sandstone

Sandstone is a naturally Sandstone is a naturally occurring compositeoccurring composite

Sandstone is also a ceramicSandstone is also a ceramic Sandstone is a rock!Sandstone is a rock!

Non-MetallicNon-Metallic InorganicInorganic CrystallineCrystalline Naturally OccurringNaturally Occurring Rock/CompositeRock/CompositeCeramic/Ceramic Composite:Ceramic/Ceramic Composite:

Natural Ceramic:Natural Ceramic:Crystalline CeramicCrystalline Ceramic

THE COLUMNS OF STEIDLE THE COLUMNS OF STEIDLE BUILDING IIBUILDING II

At low magnification, the At low magnification, the original sand (quartz) grains original sand (quartz) grains are seenare seen

The quartz grains are The quartz grains are somewhat less than 1mm in somewhat less than 1mm in sizesize

But what caused the sand to But what caused the sand to “lithify?” What material “lithify?” What material “sintered” the sand grains “sintered” the sand grains together? What is the together? What is the “cement” which binds the “cement” which binds the composite into a composite into a “monolithic” material?“monolithic” material?

THE COLUMNS OF STEIDLE THE COLUMNS OF STEIDLE BUILDING IIIBUILDING III

At high magnification, a “plate-like” phase is seen in the spaces At high magnification, a “plate-like” phase is seen in the spaces between the sand grains.between the sand grains.

The “cement” that sinters the sand grains together is called The “cement” that sinters the sand grains together is called Calcite: calcium carbonate (CaCOCalcite: calcium carbonate (CaCO33).).

ELECTRON DIFFRACTION PATTERNS—THE BEAUTY OF ELECTRON DIFFRACTION PATTERNS—THE BEAUTY OF CRYSTALLINE PERFECTION!CRYSTALLINE PERFECTION!