What is the effect of aluminum in cast iron?
ATo increase hardness above 0.5%
BTo deoxidize molten cast iron
CTo affect the machinability, ductility, and shrinkage depending on form
DTo reduce hardness by combining with sulfur below 0.5%
ESAS · Question Bank
Engineering Materials
203 questions · page 5 of 11. Answer in your head first, then check the solution.
What is the effect of silicon in cast iron?
Areduce hardness by combining with sulfur below 0.5% and increase hardness above 0.5%
Bincrease fluidity and lowers melting temperature
Csoftens iron and increase ductility below 3.25%, hardens iron above 3.25% and increase acid and corrosion resistance above 13%
Ddeoxidizes molten cast iron
Iron is said to be abundant in nature. About how many percent of the earth's crust is iron?
A10%
B5%
C20%
D8%
What is the advantage of quench hardening?
AImproved strength
BHardness
CWear characteristics
DAll of the choices
What is the lowest-temperature diffusion-hardening process and does not require a quench?
ACarburizing
BTempering
CNitriding
DHeat-treating
The ff statements are true except one. Which one?
ACarburizing does not harden a steel
BFlame and induction hardening require the use of hardenable steels
CQuench-hardened steel does not require tempering to prevent brittleness
DInduction hardening is usually most efficient on small parts
Which of the ff is a requirement for hardenizing a steel?
Aheating to the proper temperature
Bsufficient carbon content
Cadequate quench
Dall of the choices
What field of study encompasses the procurement and production of metals?
AMetallurgy
BGeology
CMaterial science
Dmetalgraphy
What do you call earth and stone missed with the iron oxides?
AHemamite
BMagnetite
CGangue
DOre
What is a coal that has been previously burned in an oxygen-poor environment?
ATuyere
BCoke
CDiamond
DHemamite
What is the most common alloying ingredient in copper?
ABrass
BZinc
CNickel
DAluminum
What refers to the casehardening process by which the carbon content of the steel near the surface of a part is increased?
ACarburizing
BAnnealing
CNormalizing
DMartempering
What is the process of heating a hardened steel to any temperature below the lower critical temperature, followed by any desired rate of cooling?
ANormalizing
BSpheroidizing
CCarburizing
DTempering
What is defined as an intimate mechanical mixture of two or more phases having a definite composition and a definite temperature of transformation within the solid state?
APearlite
BEutectoid
CAusternite
DDelta solid solution
What is the most undesirable of all the elements commonly found in steels?
ASulfur
BPhosphorus
CSilicon
DManganese
What is a method of casehardening involving diffusion in which the steel to be casehardened is machined, heat treated, placed in an air-tight box and heated to about 1000ºF?
AAnnealing
BNormalizing
CCarburizing
DNitriding
What typical penetrator is used in Brinell hardness test?
A10 mm ball
B120º diamond (brale)
C1.6 mm diameter ball
D20º needle
What is the ratio of the maximum load in a tension test to the original cross-sectional area of the test bar?
ATensile strength
BYield strength
CShear strength
DFlexural strength
What is the ratio of stress to strain in a material loaded within its elastic range?
APoisson's ratio
BRefractive index
CModulus of elasticity
DPercent elongation
What is a measure of rigidity?
AStiffness
BHardness
CStrength
DModulus of elasticity