Question

#5. An acrylic polymer is subjected to an alternating stress between 0 and 15 MPa. The largest surface cracks initially detected by nondestructive testing are 0.001 mm in length. If the critical fracture toughness, Kc, is equal to 2, calculate the number of cycles required before failure occurs. Let the geometry factor, Y, be Y = 1.0. Also, the parameters in the Paris growth law for cracks are C = 2.047 x 103 and n = 3.01 Answer: (number of cycles, N,)

please do not copy other answer .

Answer 1

{:0=15 mpa Are y Ahernaling Strees 30 to 15 MPa. к - 2. largest ООО І МҮМ surface cracks хо-3 ( - 2-оча хто М-2.0 | also, geometry factor, you Now, the Cmik@g Хtоw ѕи, а о ac Кус с. овч чтigit fracture equatic yo Jта.. Л Yo TC Kaca = 2Mpa um ти (0 2. 2MPa um 2 тхч ". * 15 ac т 225 Р X — к 1 x 15 mpa об• обS6 м с 5.6SM m) ac

Therefore, no of cycles, N=2 12-1)/2 Na 2. [6059 n/ (2-n)@gºgopa 10-6 ai coooolmm m3.01 3 aca 0.0056 m. ca 2.047810 yo1 Aos 15-0 - IS MPa Now, butting all values in above equation, 2 {(ooosol للا (1006) 22.00 (2-3.01)(20477102)()*0' (15 )2008 ce forum NA 2 (13.71 - 1071152) (-1.01) (2.044 4x1013 ) *1*3467164 x(5:6) 3 52.69 Na 2115.62 810 cycles 40147.75