Optimization of Novel Sphere Sandwich Structure for Impact Requirements

Sphere Sandwich Structures (SSS) are a new structure which may have the potentials to provide the energy absorption as compared with monolithic specimen material. By using innovation carving wax method, fifteen specimens have been prepared according to RSM optimize method and it machined by CNC-3axis machine with sphere end screw. Three factors sphere diameter(D), distance between spheres(X) and skin thickness(K) have been studied. The impact test has been achieved by Izod test to calculate specific fracture toughness. The results show the sample 642 has the highest specific fracture toughness value with an improvement of 300% compared with the monolithic sample. The optimal value of this test is 35.37 MPa m(0.5) g(-1) of the sample 682 (diameter = 6, distance between spheres = 8, skin thickness = 2 mm) with 10% error when compared with practice result at the same geometry. According to ANOVA analysis, the diameter of sphere(D) has greatest effect than other factors and then skin thickness(K).