Question

A specimen of a 4340 steel alloy with a plane strain fracture toughness of 54.8 MPa (50 ksi ) is exposed to a stress of 2431 MPa (352600 psi). Assume that the parameter Y has a value of 0.94. (a) If the largest surface crack is 0.2 mm (0.007874 in.) long, determine the critical stress . Enter your answer in accordance to the question statement MPa (b) Will this specimen experience fracture

Answer 1

a) 2325.98 MPa

b) The specimen will not experience fracture because critical stress calculated in ( a ) 2325.98 MPa < 2431 MPa

Step-by-step explanation:

Strain fracture toughness = 54.8 MPa

stress = 2431 MPa

Parameter Y = 0.94

a) Determine critical stress

Given that largest surface crack = 0.2 mm

Critical stress = 2325.98 MPa

attached below is the solution

b) The specimen will not experience fracture because critical stress calculated in ( a ) 2325.98 MPa < 2431 MPa