3. A 3-point bend specimen was tested according to ASTM E399. The Load-Displacement plot showed a...

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3. A 3-point bend specimen was tested according to ASTM E399. The Load-Displacement plot showed a Type-I behavior. The maximum load and 5% secant load were measured as Pmax = 86 kN and PQ = 80 kN, respectively. A chevron starter notch was machined, and the specimen was subjected to 30,000 cycles at Pmax = 45 kN and Pmin = 0 kN for the fatigue cycle. The final stage of fatigue crack growth was conducted for 50,000 cycles at Pmax = 30 kN and Pmin = 0 kN for the fatigue cycle. The specimen dimensions were measured as S = 30 cm, W = 8 cm, B = 4 cm, a = 3.996 cm, a2 = 4.007 cm, a3 = 3.997 cm, as 1 (surface) = 3.915 cm, a 2(surface) = 3.952 cm. Determine Kic for the material. The yield strength of the material is =1200 MPa. 3. A 3-point bend specimen was tested according to ASTM E399. The Load-Displacement plot showed a Type-I behavior. The maximum load and 5% secant load were measured as Pmax = 86 kN and PQ = 80 kN, respectively. A chevron starter notch was machined, and the specimen was subjected to 30,000 cycles at Pmax = 45 kN and Pmin = 0 kN for the fatigue cycle. The final stage of fatigue crack growth was conducted for 50,000 cycles at Pmax = 30 kN and Pmin = 0 kN for the fatigue cycle. The specimen dimensions were measured as S = 30 cm, W = 8 cm, B = 4 cm, a = 3.996 cm, a2 = 4.007 cm, a3 = 3.997 cm, as 1 (surface) = 3.915 cm, a 2(surface) = 3.952 cm. Determine Kic for the material. The yield strength of the material is =1200 MPa.