Mechanical Engineering And Sum Other Shit Flashcards
Name the 5 constraints.
- torsion
- compression
- tension
- deflection
- sheering
What is torsion?
The act of something being twisted
What is compression?
A forced being pushed from both sides of the object “Crushing” it ——>
What is tension?
Being stretched
What is deflection force?
To resist an impact being forced upon it
What is sheering?
The forcing of something tearing
Properties
What is ductility?
Ability to be drawn into a wire
Properties
What is malleability?
Ability to be shaped or flattened into a sheet
Properties
What is resilience?
Ability to resist impact
Properties
What’s is rigidity/stiffness?
Inability to be bent or forced out of shape
Properties
What is flexibility?
Will not keep its shape when subjected to a force
Properties
What is thermal conductivity?
Ability to allow heat to go through
Properties
What is electrical conductivity?
Ability to allow an electrical current to flow through
Properties
What is resistance to corrosion?
The ability to resist rusting
Ceramics
Name common properties of ceramics
Low electrical conductivity: used as insulators in electronics
Hardness: used in building materials(bricks) and for certain cutting tools
Heat resistance
Low thermal conductivity: used in ducts for fumes and water
Resistance to corrosion: used in engines
Ceramics
What causes ceramics to degrade?
Acids ( like sulphur) and bases ( like calcium hydroxide)
And variation in temperature degrade the properties of the material
Ceramics
What is used as a protection to protect ceramic from degradation?
There is no protection since practice are so durable
Plastics
What is a thermoplastic?
Plastics that can be heated and reshaped many times without losing its properties.
Plastics
What is thermosetting plastic?
Type of plastic that can only be heated and shaped once… otherwise if heated more than once it will lose its properties
Plastics
Which type of plastic is recyclable?
Thermoplastic(because they need to be heated and reshaped to be reused)
Plastics
Name 3 causes of degradation of plastics
- penetration by liquid
- Oxidation
- Ultraviolet rays
These causes makes the plastic crack and change its colour
Plastics
How can you protect plastics from degradation?
- Protection with a waterproof coating
- Adding antioxidants (fights against oxidation
- adding pigments that absorb UV rays
Links
What’s the difference between direct and indirect link?
Direct: two parts held together without a linking component
Indirect: two parts that need a linking component to hold them together
Links
What’s the difference between rigid and flexible?
Rigid: unable to bend or be forced out of shape
Flexible: linking component can be deformed(rubber,spring)