Materials Engineering Flashcards
6 cards from real BE/B Eng Bachelor of Engineering practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Materials Engineering flashcards as text
What is the crystal structure of most common metals at room temperature called?
Answer: Face-Centered Cubic (FCC), Body-Centered Cubic (BCC), or Hexagonal Close-Packed (HCP)
Most engineering metals adopt FCC (e.g., aluminum, copper), BCC (e.g., iron, tungsten), or HCP (e.g., titanium, zinc) crystal structures depending on their atomic bonding.
What is the glass transition temperature (Tg) of a polymer?
Answer: The temperature below which a polymer transitions from a rubbery to a glassy, brittle state
Below Tg, polymer chain segments lose mobility and the material becomes rigid and brittle (glassy); above Tg, the polymer is rubbery and flexible.
What is the purpose of alloying in metals?
Answer: To improve mechanical properties such as strength, hardness, or corrosion resistance
Alloying adds one or more elements to a base metal to alter its microstructure and enhance properties like strength, ductility, toughness, or corrosion resistance.
What does a phase diagram for a binary alloy system show?
Answer: The equilibrium phases present at various temperatures and compositions
A binary phase diagram maps the stable phases (solid, liquid, or mixtures) present in a two-component system across a range of temperatures and compositions.
What is the Vickers Hardness Test used to measure?
Answer: A material's resistance to permanent deformation by indentation
The Vickers hardness test presses a pyramid-shaped diamond indenter into the material surface under a defined load and measures the size of the resulting indentation to calculate hardness (HV).
What is the difference between thermoplastic and thermoset polymers?
Answer: Thermoplastics can be remelted and reshaped; thermosets permanently harden after curing
Thermoplastics (e.g., polyethylene, nylon) soften when heated and can be remolded repeatedly; thermosets (e.g., epoxy, polyester resin) form irreversible crosslinks when cured and cannot be remelted.