Materials Engineering

What are silicon-iron alloys used for in electric motors and generators?

• As permanent magnets

• For the rotor and stator cores

• To make the materials soft magnetic

• To retain magnetism when the field is removed

Tags

NGSS.HS-PS3-5

How do hard magnetic materials like high carbon steel become magnetized?

• By adding silicon or nickel to the steel.

• By cooling it rapidly (quenching) from red heat.

• By removing the magnetic field.

• By adding cobalt to the steel to make an alloy.

What can be added to steel to make permanent magnets more powerful?

• Silicon

• Nickel

• Iron

• Cobalt

Tags

NGSS.HS-PS3-5

Which term best describes the process of weakening or destroying non-metallic materials by chemical substances?

• Oxidation

• Corrosion

• Degradation

• Erosion

Which material is susceptible to degradation when exposed to prolonged contact with oil?

• Rubber

• Plastic

• Metal

• Glass

What can weaken or perish rubbers and plastics when exposed to sunlight?

• Heat

• Moisture

• Ultraviolet rays

• Chemical solvents

Tags

NGSS.HS-PS4-3

Which characteristic makes rubber and plastic materials susceptible to softening by chemical solvents?

• High tensile strength

• Low melting point

• Resilience

• Chemical reactivity

Tags

NGSS.HS-PS2-6

Which material is noted as an exception for being a good conductor of electricity despite being a non-metal?

• Silicon

• Iron

• Carbon

• Cobalt

What is the primary purpose of heat treatment in materials engineering?

• To increase electrical conductivity

• To improve mechanical properties

• To enhance optical properties

• To reduce material density

Which of the following materials is commonly used as a composite matrix in materials engineering?

• Aluminum

• Epoxy resin

• Copper

• Silicon