Science test review

Page 1

Mechanical constraints

Compression- crushing or squeezing forces( like crushing a can)

Tension- pulling or stretching force(like pulling a rope)

Torsion- Twisting something( like ringing out a towel)

Deflection- Bending force( like when you jump on a diving board)

Shearing- Cutting force( scissors)

Page 2

Mechanical properties of materials

Ceramics-properties-

Low electrical conductivity

Hardness

high heat resistance

Low/high thermal conductivity

Low resilience(break easy)

No elasticity

Chemical neutralily

Resistance to corrosion

Stiffness

Metal- properties

Hardness

Electrical/thermal conductivity

Magnetic properties

Malleability/ductility

Resisiliance (steel)

Plastics- two types Thermoplastics and thermosetting plastics

thermoplastic properties thermosetting properties- Hardness, Stiffness, Heat resistance, Corrosion resistance, No electrical conductivity, High resilience

Low thermal conductivity

No electrical conductivity

High elasticty

High corrosion resistance

High resilence

Low heat resilence

wood- properties

Hardness

Elasticity

Resilience

Poor thermal conductivity and electrical

Resistance to corrosion

Lightness relative to strength

Page 3

mechanical properties in general

Hardness- ability to resist denting/scratching (ex; a diamond)

Ductility- ability to stretch without breaking (ex; copper)

Elasticity- ability for an object to return back to its original shape( ex; a slinky)

Malleability- ability for a material to bend without breaking

Resilience- a material's ability to resist shock

Stiffness- ability for something to keep its shape

Page 4

Metal treatments

Metal coatings to prevent rust( zinc,galvanization, paint, enamel, grease, resin)

Metal finishings increase durability

Page 5

Plastics 2 types

Thermosetting plastic- doesn't become soft when heated it stays hard.

Thermoplastic- becomes soft when heated to be reshaped

Page 6

Degradation and protection of individual materials