A specimen of a 4340 steel alloy with a plane strain fracture toughness of 54.8 MPaym...
Question 10 (7 marks) Suppose that a BMW car component fabricated from 4340 steel alloy having a plane strain fracture toughness of 50 MPavm is exposed to a stress of 950 MPa. NDT results show there are two cracks. One is a surface crack of 0.60 mm long, and the other is an internal crack of 2 mm long. Will this component experience fracture? Why or why not? Assume that the parameter Y has a value of 1.0. Kjc: Plane...
A large plate is fabricated from a steel alloy that has a plane strain fracture toughness of 75 MPam (68.25 ksi vin.). If the plate is exposed to a tensile stress of 347 MPa (50330 psi) during use, determine the minimum length of a surface crack that will lead to fracture. Assume a value of 0.94 for Y. mm
1. A large plate is fabricated from a steel alloy that has a plane strain fracture toughness of 82.4 MPavm. If the plate is exposed to a tensile stress of 345 MPa during service use, determine the minimum length of a surface crack that will lead to fracture. Assume a value of 1.0 for Y. Maximum stress at tip of elliptically shaped crack Pt 2Ery, 1/2 critical stress required for crack propagation in a brittle material πα KIe YoeVra Fracture...
3. A structural component is fabricated from an alloy that has a plane-strain fracture toughness of 69 MPa, m (69 MPa square root of "m"). It has been determined that this component fails at a stress of 250 MPa when the maximum length of a surface crack is 1.6 mm. What is the maximum allowable surface crack length (in mm) without fracture for this same component exposed to a stress of 250 MPa and made from another alloy that has...
An aircraft component is fabricated from an Al alloy that has a plane strain fracture toughness of 32 MPa·m1/2. It has been determined that fracture results at a stress of 235 MPa when the maximum internal crack length is 1.8 mm. For the same component and alloy, will fracture occur at a stress level of 310 MPa when the maximum internal crack length is 0.9 mm?
1. AA 6061, a high-strength aluminum alloy, has a 0.2% offset yield strength of 37,500-psi and a plane strain fracture toughness (Kic) 26,400-psi (inch) At a service stress equivalent to 80% of the yield strength, will this structure fracture if it contains an edge crack of length 2.24-inches. Assume that the geometric factor, f, is 1.12. 2. A steel alloy, which has a plane strain fracture toughness (Kle) of 49-MPa(m) is exposed to a service stress of 1010-MPa. Is fracture...
2. An aircraft component is fabricated from an aluminum alloy that has a plane strain fracture toughness of 35 MPa m. It has been determined that fracture results at a stress of 250 MPa when the maximum (or critical) internal crack length is 2.0 mm. For this same component and alloy, will fracture occur at a stress level of 325 MPa when the maximum internal crack length is 1.0 mm? (10 points)
Deformation and Fracture Mechanics 1. (Fracture toughness) (a) An AISI 4340 steel plate has a width W of 30 cm and has a central crack 2a of 3 mm. The plate is under a uniform stress, ?·This steel has a Kic value of 50 m2. Find the maximum stress for this crack length. (b) If the operating stress is 1500 MPa, compute the maximum crack size that the steel may have without failure. 2. (Plastic zone radius) The size of...
Chapter 9 1. What is the magnitude of the maximum stress that exists at the tip of an internal crack having a radius of curvature of 2.5 x 10-4 mm (10-5 in.) and a crack length of 2.5 x 10-2 mm (10-3 in.) when a tensile stress of 170 MPa (25,000 psi) is applied? 2. A large plate is fabricated from a steel alloy that has a plane strain fracture toughness of 55 MPa m (50 ksi in.). If the plate is...
Question 1 5 points A specimen of a 4340-steel alloy which contains an edge crack of 3.0 mm is loaded under a tensile stress of 170 MPa. The stress concentration factor resulting from this loading has a value of 18.20 MPam Assume that the specimen is a one-sided cracked plate. An approximation value of the width plate is 40 mm 15 mm 20 mm 55 mm