MATERIAL SCIENCE CH 8 VOCAB

brittle 

tendency to fracture or shatter when subjected to stress or impact 

brittle fracture

occurs suddenly and catastrophically without any warning 

critical resolved shear stress

the minimum shear stress required to initiate slip on a specific plane and direction in a crystal

dislocation

defect in a crystal where atoms are out of place

ductile

ability to undergo large plastic deformations before failure

ductile fracture

deformation gives a warning that a fracture is about to happen

edge dislocation 

a type of dislocation where an extra half-plane of atoms is inserted into a crystal

elastic deformation

deformation that is temporary, will recover upon release of an applied stress

intergranular fracture

occurs along grain boundaries

microvoid

forms after necking begins, they are small cavities that form in the interior of the cross section

necking

all subsequent deformation is confined at this neck

plastic deformation

deformation that is permanent or non-recoverable after release of the applied load

resolved shear stress

an applied tensile or compressive stress resolved into a shear component along a specific plane and direction within that plane

screw dislocation

a type of dislocation where the crystal layers are shifted in a spiral pattern around a line

2nd phase boundary

dividing surface between 2 materials or phases

2nd phase particle

small particles of a different material or phase within the main material

strain

relates to displacements

stress

a measure of an applied mechanical load or force

stress concentration

the concentration of an applied stress at a small crack

stress concentration factor

a measure of how much stress increases around a flaw in a material compared to the average stress

toughness

how much energy a material can absorb before it breaks

transgranular fracture 

type of fracture that cracks pass through the grains