magnetism
THIS type of magnetism is marked by inherent dipoles in the material, making it naturally magnetic. Examples of this are iron or nickel.
What is FERROMAGNETISM?
THIS method of strengthening introduces impurities into a material, causing lattice distortion which makes it more difficult to deform.
What is SOLID SOLUTION STRENGTHENING?
Answer in two parts:
When conductors are heated, resistivity reacts in THIS way, due to increased phonon vibration. When impurities are introduced to a conductor (through solid solution mixing), the resistivity of the mixture reacts THIS way, regardless of the relative resistivities of the individual materials.
What is INCREASES and INCREASES?
Heat capacity is a measure of the amount of energy it takes to increase a substance by 1 degree Celcius. Polymers, ceramics, and metals and THIS order of relative heat capacity. (List in order of smallest to greatest)
What is:
metal, ceramics, polymer
To lower gas porosity in a casted product, THESE three methods are used.
What is:
lowering superheat
de-gassing
vacuum melting
THIS type of magnetism describes materials that only become magnetic once placed in a magnetic field. An example of this is aluminum.
What is PARAMAGNETISM?
Cold working a ductile material causes THIS, making it stronger but more unstable.
What is INTERNAL STRESS?
Conductors, semiconductors, and insulators have different energy band gaps that determine their conductive properties. THESE are the relative sizes of the gaps for each type of material. (List all 3)
What is:
conductors: no gap
semiconductors: small gap
insulators: large gap
At near 0K temperatures, the heat capacity is dependent on the temperature of the material. After THIS point, however, heat capacity is independent of it.
What is the DEBYE TEMPERATURE?
THIS method of deformation involves heating a material until soft, but not melted, and pushing it through a die with a ram.
Sensors utilize THIS type of magnetic material.
What is a PARAMAGNETIC material?
Grain size reduction strengthens materials because the increased number of THESE allows for more deflections of energy within.
What are GRAIN BOUNDARIES?
Semiconductors can be intrinsic or extrinsic. THIS marks the difference between them, and as temperature increases their resistivities reacts in THIS way.
What is:
Intrinsic are naturally semiconductors from structure. As temperature increases, resistivity decreases
Extrinsic is created from adding trace amounts of impurities, introducing excess electrons or holes. As temperature increases, resistivity increases.
Thermal expansion is when materials expand due to increases in temperature. Metals, polymers, and ceramics have THIS relative order of magnitude.
What is:
ceramics, metals, polymers
Forge welding is when different materials are joined together by hammering at elevated temperatures. This has THESE two benefits.
What is
- cool aesthetics
- can control what type of material at specific regions of product
THIS type of magnetism has no electron dipole but generates one when placed in a magnetic field.
What is DIAMAGNETISM?
After cold working, THIS process is common to increase ductility and make grain sizes smaller.
What is HEAT TREATMENT?
Extrinsic semiconductors come in two forms, p-type and n-type, which differ in THIS way. The method of adding only trace amounts of impurities to create these materials is referred to as THIS.
What is:
p-type lacks electrons, starts with holes. charge moves "along" with electric field as electrons move to fill holes.
n-type has excess electrons, charge moves "against" electric field as electrons are attracted to positive side
DOPING
THIS occurs when a material undergoes a change in temperature, but isn't allowed to expand or contract.
What is THERMAL STRESS?
The point at which a specimen breaks during a tensile test is called THIS.
What is the TERMINAL POINT?
What is the OPPOSITE DIRECTION?
category subversion: THIS type of diagram shows the relative resistances to oxidation.
What is an ELLINGHAM DIAGRAM?
Thermo-electric generators produce electricity from a change in temperature. Semiconductors are used for THIS reason instead of conductors or insulators.
What is:
conducts conduct the heat and the temperature difference would dissipate
insulators wouldn't foster flow of electrons
THIS property is a material's ability to withstand rapid changes in temperature without fracture.
What is THERMAL SHOCK RESISTANCE?
When approximating the yield strength of a material from the stress strain curve, THIS approximation is used.
What is 0.002 APPROXIMATION?