in the first video of module 1, the examples used to demonstrate the successful application of materials include ________
which of the following characteristics is not desirable for the materials used to make the helmets?
which of the following materials belong to advanced materials？
the art materials can respond to the environmental changes.
_______ is the rule in materials selection.
there are ____ components involved in the discipline of materials science and engineering.
the term materials science and engineering combine both _______ and ________.
which of the following is not the approaches used to minimize any possible adverse impacts on the environment at all stages of the materials cycle?
which of the following step(s) belongs (or belong) to materials cycles?
which of the following is not ceramics?
advanced materials include semiconductors, biomaterials, art materials and nanomaterials.
the term of ______ describes the behavior of materials when subjected to some external force or condition.
materials engineering involves, on the basis of ______ correlations, designing or engineering the structure of a material to produce a predetermined set of properties.
mse involves the generation and application of knowledge relating _____ to their _______ and uses, having interdisciplinary and multidisciplinary characteristics.
___________means that a material, after completing its life cycle in one component, could be reprocessed, could re-enter the materials cycle, and could be re-used in another component.
the art materials have the ability to respond to ____________.
the four components involved in the discipline of materials science and engineering include _____.
in selecting a material for a specific application, which of the following issues should be considered?
according to american society for testing, materials are ________ .
life cycle ysis is used to improve the environmental performance of products.
disposal/recycle is the key stage to ensure the last stage to become the first stage of the materials cycle.
the structure of a material depends on how it is processed, and a material's performance is a function of its properties.
list the groups of family of materials
the bonding type of aluminum is
o2 is a molecule
because of hydrogen bonding, hydrogen fluoride (hf) has a higher boiling point than hydrogen chloride (hcl)
when stacked together, the unit cells form the whole crystal
the periodicity of any single crystal can be described by an equivalent space lattice
in crystallography, there are eight crystal systems and 14 bravais lattices
any crystal structure changes in a material produces different properties.
tin pest occurs because of an allotropic change of tin below 13.2oc
steel is an interstitial solid solution with impurity carbon atoms in iron crystal lattice
dislocations make it easier for slip or plastic deformation to occur.
a ductile metal becomes harder and stronger as it is subjected to cold working
if a crystalline solid consists of a number of grains, such material is called
internal atoms have missing bonds, so, they are in higher energy states than surface atoms
when an alloy is at a temperature above the solidus but below the liquidus, it coexists as ___________
the gibbs rule represents a criterion for the number of phases that coexist within a system at equilibrium
the key word to describe the nature of covalent bond is of electrons
the key word to describe the nature of ionic bond is of electrons
if the unit cell contains an identical component in the center of the cube in addition to those at the corners of the cube, then it is called _________
the ability of an element to exist in different space lattices is called
when impurity atoms are found in the voids or interstices among the host atoms, it is called a/an solid solution.
when impurity atoms replace the host atoms, it is called a/an solid solution
which one is the curve that represents the temperatures at which solidification begins?
primary bonding is the forces within a molecule, while secondary bonding is the forces between molecules
in polymers, bonds inside the long chain molecules are secondary bonding, bonds among the chains are covalent bonding
long range order means the orderly arrangement of atoms extends throughout the entire material.
if you cool molten metal at extremely rapid rate, amorphous metal can form
both face-centered cubic and hexagonal close-packed are close-packed crystal structures
because of allotropy, steel can be produced from iron
the existence of point defects，impurity atoms, dislocations，grain boundary may all hinder the dislocation movement, hence weaken the materials
which equation describes the engineering strain?
what information you can find in a stress-strain diagram?
which of the below terms have same meaning?
a material subjects to a deformation under force and can go back to its original shape. we call the material undergoes an elastic deformation.
in a stress-strain diagram, which region refers to ductile property?
which statement is correct?
_____is defined as a sudden application of a load confined to a localized area of a material.
which of the below statement are correct?
high temperature may change a ductile material into brittle.
a brittle material has very little plastic deformation.
when broken, cross-section image of a ductile material has flake-like structure.
the _____ the stress is applied to the material, the less cycle it will endure before its failure.
fatigue limits of a typical ferrous alloy is about____ tensile strength.
all materials have a fatigue limit.
which statements about creep forming is correct?
creep happens at specific temperatures.
the creep rate is higher at a high temperature.
what is range of mohs scale?
which one represents the hardest sample of mohs hardness?
hard materials have good resistance to _____ and _____.
the tensile strength of steel（mpa) is about 3.4 times of that of brinell hardness.
the efficiency of a material in absorbing heat is described by heat capacity
material with high bonding energy has low thermal expansion coefficient.
which statement is correct?
_____is defined as a sudden application of a load confined to a localized area of a material.
the ______ the heat capacity, the _____ the amount of heat needed to produce a temperature change.
what are correct for describing off-set yield strength?
which statements are correct?
which of the following statements are correct?
which of the experiments are used for measuring toughness?
what are the methods of applying load in a fatigue test?
what are the typical methods for penetration testing of hardness?
for electrochemical corrosion, the cell consists of four basic components: , , , and an external conducting connection between anode and cathode
ductile materials can stand large plastic deformation without fracture.
materials with high elastic modulus are typically soft.
toughness is the ability or capacity of a material to absorb energy during elastic deformation.
a ductile material will be ductile forever.
the maximum stress that can be sustained for a specified number of cycles without fracture is called fatigue limit.
many nonferrous metals, such as aluminum and other non-ferrous metals exhibit no fatigue limit.
creep happens at specific temperatures.
higher stress or higher temperature reduces the rupture time and decreases the creep rate.
a material with high bonding energy has low thermal expansion coefficient.
what are the mechanis of thermal conductivity?
from the microstructure, atoms in metals and their alloys are arranged in a very orderly manner.
with regard to the mechanical properties, metals are typically hard, also relatively stiff and strong when in solid state.
from the iron-carbon phase diagram, which of the following phases/phase combinations is present for a steel composition of 0.7wt % c at 700°c
the eutectic concentration of carbon is 0.76%
________ is usually performed after quenching
the primary purpose of briquetting is to
are made with a p/m process
according to carbon content, the steels are classified into low-carbon, medium-carbon, and high-carbon types.
cast iron is the most widely used engineering material, and also the most recycled of all materials
refractory metals include niobium (nb), ________, ________, and ________
for brasses, tin is the predominant alloying elements as substitutional impurity.
refractory metals are those metals which have extremely low melting temperatures
magnetostrictive materials can convert energy into kinetic energy, or the reverse
the magnetic shape memory effect results due to martensitic phase change to austenite phase at higher temperature
amorphous metals are non-crystalline, and have a glass-like structure. like common glasses, amorphous metals are electrical insulators.
all alloys that are not______ based, are called nonferrous metals
which of the following do not belong to non-ferrous metal?
cast iron can be classified into four categories: gray cast iron, white cast iron, nodular cast iron and ______ cast iron
most cast irons have a chemical composition of ______ percent carbon
the predominant alloying element in stainless steel is ______, which concentration should be higher than 11 wt%.
______ is one of the principal alloying elements in stainless steels, and one major constituent in superalloys.
metals are good conductors of both______________
are not made with a p/m process.
which is not involved in the general pm production steps.
______ is believed “the most glamorous metal in the world”
al-li alloys not only have a very high , but also have excellent fatigue and low-temperature toughness properties.
stainless steels are ided into three classes on the basis of the predominant phase constituent of the microstructure: ________, ________, or________
uses cooling in still air？
some general corrosion protection techniques include material selection, ___________, ___________, and___________
compared with ferrous alloys, nonferrous metals are much lighter, and have lower conductivity.
the phase diagram contained only two components is known as binary diagrams.
annealing and normalizing present a significant difference on the ductility of low carbon steels.
tungsten light bulb filaments should be fabricated by p/m process.
in corrosion process, the total rate of oxidation must equal the total rate of reduction.
what is the main difference between precipitation hardening and the quenching?
ceramics based primarily on the natural raw materials of clay and silicates are ________
advanced materials include , exhibit specialized properties.
the main source of quartz is .
the crystalline structure of silicon carbide is with alternating si and c atoms covalently bonded together
ceramics can be produced at than that of competing metal-alloy components.
clay is a complex mixture of .
sand consists of fine particles of quartz.
grinding is accomplished by confining the ceramic powder, this process can be called a .
sintering furnaces usually heat ceramic compacts externally by following thermal transfer.
a major problem in ceramic processing is achieving the same properties every time when a process is repeated.
traditional processing for fabricating ceramic is .
following water, which free of organic matter, can be used to prepare concrete.
portland cement is termed a hydraulic cement because its hardness develops by chemical reaction with .
the most expensive glass is .
amorphous materials do not have clearly defined freezing or melting points as do crystalline materials.
3d printing or additive manufacturing is a process of making solid objects from a digital file.
3d printing is the process of increasing manufacturing steps.
a major objective in designing new ceramics is to overcome
the term describing the density of ceramics that includes its porosity and both crystalline and noncrystalline phase is_____________.
in cold step, the ceramic part is formed or shaped into a preform, which called .
the main driving force in sintering process is .
when some liquid is formed during processing, we call it_____________.
some flaws can occur at any of sintering stages, which consist of .
_________ is considered as the glass former.
__________ is now required on doors in buildings and homes.
slower cooling permits some crystallization in the process, we call it________.
bonding in ceramic materials is________________.
the basic unit of the silicate structure is the sio4 tetrahedron, which is formed by:
there are two factors influencing the density of material.
the pores affect the strength of ceramics in the following ways including ______.
ceramic process can be simply described as consisting of two steps: and .
3d printing enables us to produce complex (functional) shapes using two steps with ______and ______ than traditional manufacturing methods.
glass can also be sorted to advanced ceramics in certain conditions.
setting and hardening are caused by the chemical reactions between the cement and water.
what are the differences between setting and hardening? the strength after hardening is higher than that of setting?