Design optimization of carbon/epoxy tibia fracture plate using finite element simulation data
摘要
To facilitate the healing process in a tibia fracture, the fracture plate should have higher axial movement with lesser twist of the plate at the fracture site along with well-distributed lower stress in the plate and the bone. To achieve these attributes, carbon/epoxy fiber-reinforced laminated composite bone plate is studied as a transverse fractured human tibia shaft of 3-mm fracture gap. Taguchi design of experiment (DOE)-guided finite element analysis results of L32 orthogonal array are used by multi-criteria decision making (MCDM) techniques such as integrated fuzzy AHP–TOPSIS and find out the average performance index to achieve the desired stress distributions and movements. Taguchi optimization method is employed to find the fiber orientations of each lamina for achieving the target properties, which are validated further through finite element analyses. It is found that among the 32 DOE-guided simulations the experiment number 1 having stacking sequence of [−45°/−45°/−45°/−45°/−45°/−45°/−45°/−45°/−45°]S with 0.2 mm lamina thickness is ranked 1 for multi-criteria optimization considering average performance index 0.643106 which also has the maximum axial movement of value 0.291 mm and minimum stress on the plate with 84.378 MPa. Lesser value of stress on the cancellous bone (1.461 MPa) obtained in the exp. no. 32 with the layer orientation is [90°/90°/0°/−45°/45°/−45°/45°/90°/0°]s and thickness 2.5 mm. Lower value of twisting angle (0.3775658°) and stress (15.347 MPa) in cortical bone are obtained using Taguchi optimization method with the layer orientation of [90°/90°/90°/90°/90°/90°/90°/90°/90°]s and [90°/90°/90°/90°/90°/−45°/−45°/45°/45°]s having thickness of 2.5 mm.