Question

Alarge plate is fabricated from a steel alloy that has a plane strain fracture toughness of 82.4 MPa m1/2. If the plate is exposed to a tensile stress of 345 MPa during the service use, determine the minimum length of a surface crack that will lead to fracture. Assume a value of 1.0 for Y.

Answer 1

minimum length of a surface crack is 18.3 mm

Step-by-step explanation:

Given data

plane strain fracture toughness K = 82.4 MPa m1/2

stress σ = 345 MPa

Y = 1

to find out

the minimum length of a surface crack

solution

we will calculate length by this formula

length = 1/π ( K / σ Y)²

put all value

length = 1/π ( K / σ Y)²

length = 1/π ( 82.4
`10^(3/2)` / 345× 1)²

length = 18.3 mm

minimum length of a surface crack is 18.3 mm