EC52FC1 - Agustin - Engineering Materials

8/12/2019 EC52FC1 - Agustin - Engineering Materials

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CHOICES

1 ________ are molecules that have the same composition,

but different structure.a. Isomers

b.Polymers

c.Isotactic

d.Atactic

2 The supplied energy for the removal of electrons. a.Ionization energy

b.Affinty energy

c.Electron affinity

energy

d.Light energy

3 It implies repetition of objects at regular intervals a.Translation

b.Lattice points

c.Symmetry

d.Bilateral

4 The intense beam produced by an X-ray are known

as__________.

a. Refracten beam

b.Beam width

c.Incident beam

d.Diffracted beam

5 __________ corrosion is commonly seen in rivet heads,

bolts, weld joints, and gasket opening.

a. Galvanic

b. Crevice

c. Pitting

d. Intergranular

6 In the processing techniqes for composite materials. It is a

continous process where certain uniform cross sections are

produced.

a. Pultrusion

b.Filament winding

c.Injection moldingd.Diffusion bonding

7 "Silicates" with organic side radicals; thus silicon-based

polymeric molecules.

a. Silicone

b. Silicates, sheet

c. Silicates, chain

d. Silicates, network

QUESTIONS

ENGINEERING MATERIALS (


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8 Finite group of atoms bonded by strong attractive forces. a. Electron

b. Proton

c. Quarks

d. Molecule

9 __________ are two or more distinct types of crystal that

have the same composition.

a. Isomers

b.Polymorphs

c.Isothersd.Crystalline

10 Glass coating on ceramics. a. Glaze

b.Porcelain enamel

c.Fining

d.Vitreous enamel

11 The prime optical property for glass lenses.a. Index of diffraction

b.Index of refraction

c.Ionization index

d.Angle of reflection

12 Polymerization by a reaction that also produces a small bt-

product molecule.

a. Polymerization,

addition

b. Polymerization,

multiply

c. Polymerization,

condensation

d. Polymerization,

ox dation

13 The vulcanization of rubber involves a ___________ ofadjacent molecular chains, thus resulting in a harder

rubber.

a. Cross-linkingb.Branching

c.Networking

d.Structure

14 A long term load above the glass-transition temperature of

a polymer produces____________.

a. Stress relaxation

b.Scission

c.Creep

d.Relaxation time

15 Coefficient of flowability which is the reciprocal of viscosity. a. Elastomer

b.Density

c.Crystallinity

d.Fluidity

16 Reduction of polymers to smaller molecules. a. Deformation

b.Diffraction

c.Degradation

d.Diffusion


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17 Additive used for the purpose of strengthening on/or

extending the basic polymer.

a. Plasticizers

b.Stabilizers

c.Fillers

d.Colorants

18 __________ is made by laminating separate pliesalternately at right angles to one another.

a.Hardwoodb. Softwood

c. Plywood

d.Laminated wood

19 Unoccupied space between atoms or ions. a. Interstice

b.Ionic radii

c.steatite

d.Micro cracks

20 Wood product built up from thinner boards. a. Hardwood

b. Softwood

c. Plywoodd. Laminated wood

21 Insulating materrial made from talc+clay a. Steatite

b. Ternary

c.Interstice

d. Vitreous

22 A cubic lattice with the center position fully equivalent to

each of the eight corners.

a. bcc

b.fcc

c.Hard-ball modeld.Atom

23 The total permanent strain prior to fracture measured as

elongation or as reduction of area. a. Plastic deformation

b.Elastic deformation

c.Dislocation

d.Ductility

24 __________ is the force per unit area. a. Strain

b.Stress

c.Young's elastic

modulus

d.Yield strength


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25 Large Molecules of nonmetallic elements composed of

many repetetive units. Commonly called plastics.

a. Insulator

b.Glass

c.Polymers

d.Insulator

26 Body-centered cubic iron, or an iron alloy based on itsstructure.

a. Ironb.Martensite

c.Ferrite

d.Steel

27 Low alloy steels contain as much as ___ percent of metallic

elements other than iron.

a. 2

b.3

c.4

d.5

28 Polymer with a large elastic strain. a. Isomers

b.Polymers

c.Isotactic

d.Elastomer

29 At the glass-transition temperature of a polymer, there is a

change in the ________ a. Melting point

b.Thermal expansion

c.Thermal condutivity

d.Heat temperature

30 The process of pouring a liquid metal into a mold, or theobject produced by this process.

a. Refiningb.Machining

c.Casting

d.Annealing

31 The formation of new, annealed grains from a previously

strain-hardened solid.

a. Forging

b.Recrystallization

c.Annealing

d.Refining

32 Hardening by the formation of clusters prior to precipitation.

Also called, age hardening.a. Precipitation

hardening

b.Precipitates

c.Solution hardening

d.Solidify


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33 An alloy of copper and nickel. a. Cuppronickel

b.Cupronickel

c.Cupronikel

d.Cuppro-nickel

34 The polarization of a _______ material can be changed by

a stress that intruduces an elastic strain

a. Resistive

b.Piezoelectric

c.Magnetic

d.Ferroelectric

35 A material or device that converts energy from one form to

another, Specifically electrical energy to or from

mechanical energy.

a. Dielectric

b.Transducer

c.Converter

d.Ferromagnet

36 A material that can be place between two electrodes

without conduction.a. Dielectric

b.Transducer

c.Converter

d.Ferrimagnet

37 An antiferromagnetic materials have fully balanced

alignment, and therefore no net magnetism.

a. Ferrites

b.Ferroelectric

c.Ferrimagnetism

d.Ferruma netism

38 _______is a unit of deformation a. Stress(s)

b.Strain(e)

c.Strength(S)

d.Yield point(YP)

39 (In plastic deformation) An index of a resistance that a

material has to penetration and to scratching.

a. Ductility

b.Sotness

c.Lamination

d.Hardness

40 Since Poison's ratio is less than 0.5, the volume of abronse block ________ when load in axial compression

a.Decreasesb.Increases

c.no change

d.double

41 These elements are located in the left and lower portions of

a periodic tables as conventionally presented.

a. Metals

b.Non metals

c.Gas

d.Li uid


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42 The reciprocal of electrical conductivity a. Electrical

conductivity

b.Electrode potential

c.Electrical resistivity

d.Electrical

43 Temperature at the intersection of two liquid solubility

curves.

a. Eutectic

temperature (Te)b.Eutectic

composition (Ce)

c.Eutectic pressure

44 Steel containing up to 5% alloying elements other than

carbon.a. Steel, plain-carbon

b.Steel, low-alloy

c.Steel, specialty

d.Spheroidite

45 Repelling force of too many electrons in the same vicinity. a.Electron-hole pair

b.Electronegativityc.Electron repulsion

d.Electroplating

46 Twisting and/or kinking of a polymer chain. a. Conformation

b.Configuration

c.Conductivity

d.Copolymer

47 Solid dissociation to gas and another solid. a. Carbide

b.Carburize

c.Calcination

d.Cast iron

48 A large casting that is to be consequently rolled or forged.a. Ingot

b.Induction hardening

c.Inhibitor

d.Injection molding

49 The reciprocal of electrical resistivity.a. Electrical

conductivity

b.Electrode potential

c.Electrical resistivityd.Electrical

inductance

50 The assumption that atoms are hard spheres. a. Micro-ball model

b.Soft-ball model

c.Hard-ball model

d.Mini-ball


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ANSWER DISCUSSION

a.Isomers

a. Ionization Energy

c. Symmetry

d.Diffracted beam

b. Crevice

a. Pultrusion

a.Silicone

Creviceis a localised corrosion attack that

occurs in the presense of stagnant liquids. It

is of industrial significance bacause

stainless a quite susceptible to this form of

corrosion.

Pultrusion is a continous process where

certain uniform cross-sections are produced.

The resin coated fibers are pulled through a

heated mould and curing is done during

shape information. Finally, it is cut into

desired lengths.

Silicone

This family of materials lies between

ceramics and polymers, in as much as they

have some of the characteristics of each.

Isomers, for example, are two

configurations of the same molecular

composition. For figure shown below the n-

and iso-propyl alcohol, both. C3H7OH. H

O

H H H H I H

HC-C-C-OH HC-C-CH

H H H H H H

n-propyl alcohol isopropyl alcohol

ahtematics Category)

Ionization energyis a measure of how

strong the electron is bounded to the atom.

The energy required to remove the first

electron is the first ionization energy.

Similarly, the energy required to remove the

second electron is the second ionization

energy.

Those operations which can describe the

repitition of objects are known as symmetry

operations.

The scattered X-rays propagating in all

directions may reinforce each other in some

directions to produce intense beams of X-

rays. These strong beams are known as

diffracted beam.


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d.Molecule

b.Polymorphs

a. Glaze

b. Index of refraction

d. Polymerization,

condensation

c.Cross-linking

a.Creep

d.Fluidity

c. Degradation

Index of refraction

Ratio of light velocity in a vacuum to the

velocity within a material. (Produces a

"bending" of the light at the surface of amaterial).

Polymerization of molecules (monomers)

into extended molecules (polymers) is

accomplished by two principal types of

reaction. These are

(a) By chain reaction (also called Addition,

polymerization), and

(b) by step reaction (also called

The vulcanization of rubber involves a cross-linkingof adjacent molecular chains, thus

resulting in a harder rubber.

The vulcanization of rubber is a result of

cross-linkingby sulfur. Without sulfur,

rubber is a soft, even sticky material that

flows by viscous deformation when it is near

Creep

Slow permanent deformation. In polymers,

this is by viscous flow above the glass-

transition temperature.

Glass-transition temperature is the

transition temperature between a super

cooled liquid and its glassy solid.Viscosity, which is the ratio of shear stress

to the flow gradient, is the reciprocal of

fluidity

Degradation

Destruction/Reduction of polymers to

smaller molecules

A molecule may be defined as a group of

atoms that are strongly bounded together,

but whose bonds to other, similar groups of

atoms are relatively weak.

Polymorphs are two or more distinct types

of crystal that have the same composition.

The most familiar example is the dualexistense of graphite and diamond as two

polymorphs of carbon

Veneers of glass have extensive use:

Glazes- Glass coating on ceramics products

Vitreous enamels/ porcelain enamels-

Glass coatings on metal


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c.Fillers

c.Plywood

a.Interstice

d.Laminated wood

a. Steatite

a. bcc

a.Ductility

b.Stress

Ductility

Is the total plastic strain, that is accumulated

prior to fracture. This may be mesured as

the unit stretching called elongation, or as

the cross section contraction, called

reduction in area. Both are dimensionless

and usually expressed in percent.

Stress

In order to define the effect of loads upon

materials, we speak of stress, which is is

the force, F, per unit area, A:

S=F/A

Fillers

Most of them are added to give strength or

toughness to plastics.

Thus, wood flour (a very fine saw dust) is

commonly added to a PF plastic (phenol-

formal dehyde) to increase its strength.

PlywoodPanels made from laminated plies; each ply

cut is longitudinal-tangential sheet; alternate

pliesare laid at 90degrees.

Interstice

Is relatively a hole that exist in the center of

the unit cell

Laminated wood

is a composite of a no. of smaller board

bondedinto a larger unit. Thus, it is possibleto build up large beams, arches, and

columns, and to make special shapes, such

as chair frames and aircraft propellers.

Ceramics are commonly involve three(3)

components than do metals. A common

electrical porcelain (called Steatite) is made

by mixing clay with talc, and then firing the

product.

Body-centered cubic (bcc metal)

The iron atom in a car fender are most

stable when each individual iron has eight(8) neighbors. If each of the eight atoms

surronding the initial atom also has eight

neighbors, and likewise for those neighbor's

neighbors, a long-range order is established

throughout the metal.


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c. Polymers

c. Ferrite

d.5

d.Elastomer

a.Thermal expansion

c.Casting

b.Recrystallization

a.Precipitation hardening

Thermal Expansionof materials with

comparable atomic packing vary inversely

with the melting temperatures of those

materials. At the glass-transition

temperature of a polymer, there is a change

in the thermal expansion.

CastingFrom refining, it is the next step in metal

production which is to cast metal as an

ingot. Or to mold it directly into the desired

shape. An ingot is simply a large solidified

mass of metal that can susequently be

mechanically deformed by rolling of forging.

Annealing a cold-drawn wire produces a

change in properties because the internal

structure of the wire is changed. When

annealing follows cold working, the metal is

recrystallized. That is, new crystals formwithin the wire

Annealing- process of heating and cooling

to reduce fracturinPrecipitation hardening, is also called age

hardening, is a very important strengthening

process when it is applicable.

Polymers

Large Molecules of nonmetallic elements

composed of many repetetive units.

Commnly called plastics.Polymers are

characterized by their low density and their

use as insulators, both thermal and elctrical.

Ferrite (metals)Body-centered cubic iron, or an iron alloy

based on its structure.

Low-alloy steelscontain alloying elements

in addition iron and carbon. Commonly used

alloying elements include manganese (Mn),

nickel (Ni), chromium (Cr), molybdenum

(Mo), and silicon (Si), plus others. Typically,

the amounts of these alloying elements total

less than 5%.

Elastomer

Polymer with a large elastic strain. This

strain arises from the unkinking of the

polymer chain


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a.Cupronickel

b.Piezoelectric

b.Transducer

a.Dielectric

c.Ferrimagnetism

b.Strain(e)

d.Hardness

a.Decreases

a.Metals

Hardness

Is an index of a resistance that a material

has to penetration and to scratching. It is

related to the ultimate strength, since both

involve plastic deformation.

Poison's ratio (v)Ratio (negative) of lateral strain to axial

strain.

Metals

Materials characterized by their high

electrical and thermal conductivities

because their electrons are mobile.

The interrelationship between polarization

and strain provides a basis for transducer

device that convert mechanical energy to

electrical, and vice versa.

Dielectric

an insulator. A material that can be placed

between elecctrodes without conduction.

Ferrimagnetism

Net magnetism arising from unbalanced

alignment of magnetic ion within a crystal.

(An antiferromagnetic materials have fully

balanced alignment, and therefore no net

Strain(e)

Is a unit of deformation.Elastic strain is

recoverable; plastic strain is permanent

Alloys of copper and nickel are completely

soluble across the full composition range.

Both copper and nickel are fcc; furthermore,

their atomic radii match within a few percent-

Rcu= 0.1278nm, and Rni= 0. thus, an

unlimited number of copper atoms may be

replaced by nickel atoms and vice versa in

Piezoeelectric

Dielectric materials with structures that are

asymmetric. So that their centers of positive

and negative charge are not coincident. As a

result, the polarity is sensitiveto pressures

that change the dipoles distance, and the


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c.Electrical resistivity

. Eutectic temperature (Te

b. Steel, low-alloy

c.Electron repulsion

a.Conformation

c.Calcination

a.Ingot

a.Electrical conductivity

c.Hard-ball model

Calcining, that is, heating to dissociate the

structure and drive off a gas, for example,

CO2 or H2o.

Ingot

Is simply a large solidified mass of metal

that can subsequently be mechanically

deformed. By rolling or forging.

Electrical conductivity

Coefficient between charge flux and electric

field. The reciprocal of electrical resistivity.

Hard-ball model

The assumption that atoms are hard

spheres. This is a very useful concept.

However, it is not universally applicable,e.g.,

for neutron radiation exposure.

Electrical Resistivity

Resistance of a material with unit

dimensions.The reciprocal of electrical

conductivity

Eutectic temperature (Te)

Melting temperature of an alloy with aeutectic composition.Temperature at the

intersection of two liquid solubility curves.

Steel, low-alloy

Steel containing up to 5% alloying elements

other than carbon. Phase equilibria are

related to the Fe-C diagram.

Electron repulsion

Repelling force of too many electrons in thesame vicinity. Counteracts the attractive

bonding force

Conformation

Twisting and/or kinking of a polymer chain.

(Changes require bond rotation only)

EC52FC1 - Agustin - Engineering Materials

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