A. If the largest internal crack in a polycarbonate sheet is 0.100mm long and there are no surface cracks, what is the failure stress? Take Y = 1.30. Polycarbonate has a fracture toughness of2.20 MPa*m^.5
B. A plate of 1040 steel fails at a stress of 380 MPa
What is the length of the largest internal crack present on this plate? You can assume there are no surface cracks. The fracture toughness is 54.0 MPa?m1/2 and Y = 1.60.
C. A particular polymer has a critical stress intensity parameter of 5.00
MPa?m1/2 and a strength of 150 MPa. It is being used as a plate that experiences tension. The maximum stress it is designed to experience is 80.0% of its strength. You are inspecting this plate, and the minimum crack length you can detect is 1.40mm . For calculations use Y = 1.20. Calculate the maximum stress you will certify this plate to withstand.