Issue 50

M.R.M. Aliha et alii, Frattura ed Integrità Strutturale, 50 (2019) 602-612; DOI: 10.3221/IGF-ESIS.50.51 607 Figure 6 : Comparison of K Ic values obtained for front and side regions of the tested bones. Figure 7 : Variations of fracture energy ( G f ) for different SENB samples manufactured from the left and right bovine femur. Fig. 7 also presents the variations of fracture energy ( G f ) for the tested SENB specimens made of bovine bone. The average of fracture energy was determined about 0.055 J for the tested SENB specimens made of bovine bone. However, the standard deviation and scatter of fracture energy results are greater than the fracture toughness data. Variations of ( K Ic ) 2 versus G f for the whole experimental results of this research have been also plotted in Fig. 8. It is seen that there is a linear relationship between these two fracture parameters in the investigated bone that supports the well-known relation in the framework of linear elastic fracture mechanics (LEFM) between the stress intensity factor and fracture energy. According to the experimental findings of this research, the fracture index i.e. ( Ic K ) G f  ratio for the tested bovine femur is approximately equal to 33. This index that is related to the well-known mechanical properties of the bone (such as elastic modulus, Poisson's ratio, tensile strength density and etc.) can be used for estimating the corresponding value of fracture toughness in terms of the fracture energy value and vice versa. The trajectory of fracture path for the whole samples given from 0 2 4 6 8 10 K IC (MPa√m) Front region of bone Side region of bone 0 0,02 0,04 0,06 0,08 0,1 0,12 1 3 5 7 9 11 13 Fracture Energy (J) Specimen Number Average Left Bone Right Bone