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Flashcards in constraints and deformations Deck (31):
1

what is hardness
what is stiffness
difference

hardness resists denting and abrasion
stiffness maintains shape when constrained

2

what is resilience

resists shock and impact without deforming

3

what is malleability

compressed without breaking (flattened or bent)

4

what is ductility

pulled into wire or stretched (tension) without breaking

5

what is corrosion resistance

resists smoke salt and chemical products, oxidation rust

6

what are the 5 constraints? explain

compression: squeeze crush
tension: lengthens material
torsion:twists
deflection:bends
shearing:cuts

7

what are the deformations

elastic (returns to original shape)
plastic (new shape)
fracture (breaks)

8

what are plastics made from

oil and coal (fossil fuel)

9

what are fossil fuels made up of

monomers which together make polymers

different polymers form different plastics

10

what are some reasons to use plastic

durable
lasts long
inexpensive
transparent
lightweight
flexible or not

11

what are the categories plastic comes in

thermal plastics and thermosetting

12

explain Thermo plastics

become soft when heated melded or reminded then hardens

13

explain Thermo setting

remains permanently hard even when heated. add monomers to a mold once hardens cannot change. doesn't recycle

14

signs of degradation in plastics

cracking and change in colour

15

how to protect plastics from degradation

add water proof coating (penetration of liquid)
add anti-oxidants (oxidation)
add dark pigments to absorb un rays (ultraviolet rays)

16

how are ceramics made

inorganic compounds are heated extremely, the water evaporates and forms bonds between compounds

17

what are the properties and use of ceramics

low electrical conductivity:insulators in electronics
hardness: building materials (bricks and tiles)
heat resistant: kitchen appliances heat shield
resistant to corrosion: ducts for fumes or coolant
resilient:used in engines

18

how protect ceramics

avoid exposure

19

what are composites

multiple materials used or combined to get a mix of properties (metals >alloys)

20

what are composites composed of

Matrix and reinforcements

21

what would a matrix be compared to

skeleton

22

what would reinforcements be compared to

muscle and fat

23

what are some properties that plastic matrix have

durable light cheap resilient

24

metallic matrix properties

ductile stiff conductive

25

ceramic matrix properties

durable heat resistant

26

what are some reinforcements

Fiberglass, Aramid fibers and Carbon fibers

27

what are some ways alloys or metals can degrade

oxidization (rust) chemically alter is exposed to elements like acid rain salt and oxygen

28

ways to protect metal and alloys

coating with other metals and paint enamel grease or oil
antioxidants to avoid rust (blocks oxygen)

29

what are conifers

soft wood trees that grow rapidly also known as every greens

30

what are deciduous trees

hardwood trees that grow slowly

31

what are some mechanical properties

hardness
resilience
malleability
ductility
stiffness
corrosion resistance