Equation 12 · Part 1 · Why Materials Fail: Fracture, Flaws and the Inspection Interval
Symbol σ
What this part means
the applied stress.
Its job in the formula
σ is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Full expression→Symbol σ→Article meaning
Where the article explains it
Here is the applied stress, a the crack size, and Y a dimensionless factor capturing geometry and loading.
The passage around this formula
Here is the applied stress, a the crack size, and Y a dimensionless factor capturing geometry and loading. The claim embedded in this expression is a similitude claim: two cracked bodies of different shape and size, loaded differently, have the same crack-tip conditions if they have the same K . Fracture then occurs when K reaches a material-specific critical value, the plane-strain fracture toughness .
Learn the underlying idea
A variable is a named place for a value. Its letter is a local label: x can mean position in one formula and a data point in another.
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