A steel with a critical fracture toughness of 150 MPa. m1/2 has a yield strength of 1500 MPa. If fracture were to take place at the yield stress, answer the following questions. Surface crack size at yielding leading to failure is:.
a. 0.497 cm
b. 0.994 cm
c. 0.32 cm

c.

Explanation:

From the given information:

Critical fracture toughness = 150 MPa.

yield strength = 1500 MPa

surface crack size = ???

The formula for the fracture toughness is can be expressed as:

replacing our values to solve for the surface crack size, we have:

= 0.0564²

= 0.0032 m

= 0.32 cm

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