Question

A structural component in the shape of a flat plate 29.6 mm thick is to be fabricated from a metal alloy for which the yield strength and plane strain fracture toughness values are 535 MPa and 38.5 MPa-m1/2, respectively. For this particular geometry, the value of Y is 1.5. Assuming a design stress of 0.5 times the yield strength, calculate the critical length of a surface flaw. mm

Answer 1

Answer:

2.93 mm

Explanation:

Plane strain fracture toughness $K_{IC}=38.5 Mpa\sqrt{m}$

Yield strength, $\sigma=535 Mpa$

Design stress=0.5*535=267.5 Mpa

Dimensionless parameter Y=1.5

Critical length of surface flaw is given by

$a_c=\frac {1}{\pi}\times (\frac {K_{IC}}{Y\sigma})^{2}=\frac {1}{\pi}\times (\frac {38.5}{1.5*267.5})^{2}= 0.00293\approx 2.93 mm$