Question

In the construction of a large reactor pressure vessel, a new steel alloy with a plane strain fracture toughness of 55 MPa-m1/2 and a Y value of 1.0. An in-service stress level of 200 MPa has been calculated. What is the length of a surface crack (in mm) that will lead to fracture

Answer 1

Answer:

$l=24mm$

Explanation:

From the question we are told that:

Plane strain fracture toughness of $T=55 MPa-m1/2$

Y value $Y=1.0$

Stress level of$\sigma =200 MPa$

Generally the equation for length of a surface crack is mathematically given by

$l=\frac{1}{\pi}(\frac{T}{Y*\sigma})^2$

$l=\frac{1}{3.142}(\frac{55}{1*200})^2$

$l=0.024m$

Therefore

in mm

$l=24mm$