Galileo did early materials science research

after he was confined to his home. He figured it was unlikely to be controversial and get him in more trouble.

Tags: materials history galileo
Added: 2012-04-10T16:33:59Z by anders
Strain

Proportional increase in length due to stress (e = increase/original = I/L)

Tags: materials physics strain
Added: 2012-04-10T16:33:58Z by anders
Stress

Force / Area that the force acts over (s = load/area = P/A)

Tags: materials physics stress
Added: 2012-04-10T16:33:58Z by anders
strength of a material

defined as the stress required to break it

Tags: materials physics stress
Added: 2012-04-10T16:33:58Z by anders
Young's Modulus
stress near an elliptical hole

specified by Inglis: s(1 + 2*sqrt(L/r))

Tags: materials physics stress
Added: 2012-04-10T16:33:58Z by anders
Factor of Safety

number of times material strength is higher than expected working load

Tags: materials physics stress safety
Added: 2012-04-10T16:33:58Z by anders
imping

repairing a broken feather with a needle and glue

Tags: falconry
Added: 2012-04-10T16:33:58Z by anders
the roman army required officers in charge of catapults to have a good musical ear

so they could assess the tensions of the ropes by ear

Tags: materials physics tension history catapults
Added: 2012-04-10T16:33:58Z by anders
african deer can snap a hind leg through muscular spasm when startled by a lion

that’s how strong muscles are compared to bones

Tags: materials bones stress
Added: 2012-04-10T16:33:58Z by anders
bone fractures in elderly

due more to loss of nervous control than weakened bones (only a 22% reduction in bone strengh)

Tags: materials bones aging medicine
Added: 2012-04-10T16:33:58Z by anders
critical griffith crack length

L-sub-G: Point at which cracking system goes from consuming energy to releasing. 12 * 2 * WE / (strain energy)^2

Tags: materials physics stress
Added: 2012-04-10T16:33:58Z by anders
necking

form of fracture where material deforms plastically before breaking in tension

Tags: materials physics stress tension
Added: 2012-04-10T16:33:58Z by anders
work of fracture

or “fracture energy”: “toughness”, quantity of energy required to break a given cross-section of material

Tags: materials physics stress
Added: 2012-04-10T16:33:58Z by anders
resiliance

the amount of strain energy that may be stored in a structure without causing permanent damage.

Tags: materials physics strain structures
Added: 2012-04-10T16:33:58Z by anders
ancient greek chariots used flexible wheels

made from springy wood and only four spokes. worked like a bow to absorb shock.

Tags: materials physics stress history chariots
Added: 2012-04-10T16:33:58Z by anders
rust can strengthen a rivet joint

it expands and spreads the shearing forces across a larger area.

Tags: materials physics rivets rust
Added: 2012-04-10T16:33:58Z by anders
truss

any triangulated lattice girder

Tags: materials structures
Added: 2012-04-10T16:33:58Z by anders
"in the bias direction"

at 45 degrees to the warp/weft of a fabric

Tags: materials structures fabric
Added: 2012-04-10T16:33:58Z by anders
naming of the America's Cup

the yacht America won the race (which was then named for it) largely because American sail makers used tighter woven fabrics with the weave arranged to align tensions with the fibres while the brits used loose woven flax sails arranged haphazardly. The American sails allowed the yacht to sail in higher winds and turn in a tighter radius. When the Queen was told that America had come in first, she asked who came in second and was informed that no other ships were yet in sight.

Tags: history sailing sails materials structures fabric
Added: 2012-04-10T16:33:58Z by anders