1. Consider three high strength metallic alloys which are proposed for fabrication of support beams in a space shuttle launch station with following mechanical properties: Alloy Yield Stress (MPa) Alloy steel (ASTM A514F Grade) 780 Titanium allo (Ti-6A1-4V) Nickel A110 (IN-792) 1060 a. Assuming the safety factor of 2 for yield stress, calculate the maximum allowable working stress for each alloy. (2) b. Calculate the maximum internal and surface crack lengths allowable for these alloys before they experience fast and uncontrollable fracture if they are loaded to a stress of 400 MPa. (Assume that the value of Y is 1 and 1.12 for internal and surface cracks, respectively) (/6) 0. Due to the critical role of support beams in the launch stations, they are regularly tested using nondestructive testing methods (NDT) to check for possible crack and aws. Assume that the aw size resolution limit of the nondestructive testing program available is 2.0 mm for surface aws and 3 mm for internal flaws. Considering this and results of parts (a) and (b), which one of these alloys would you propose for this application. (f2)