| dc.description.abstract | Material failure is very common since the dawn of human civilization. There are many reasons that cause material failure, one of which is cracking. This research is about the stress intensity factor of surface cracking as one of the parameters to determine the effect of cracks, notches, and changes in geometry on the magnitude of the stress.
This research is about stress intensity factor simulation to understand the effect of variations in the ratio of the crack aspect ratio (a/c), the ratio of notches over small diameters (r/d), and the ratio of large diameters over small diameters (D/d) on the value of SIFs, K1 due to tension load and SIFs K2 and K3 due to torsion load. The methods used are the finite element method (FEM) and the dual boundary element method (DEBM) to validate the model. The a/c crack depth ratio was varied at 0.5, 1.0, 1.5, and 2.0, the r/d ratio was varied at 0.050, 0.075, 0.100, 0.12, while the D/d ratio was varied at 1.2, 1.5, 1.8, 2.0.
The result of this research shows that variations of a/c, r/d, and D/d have an effect on changes in the value of SIFs. The highest and lowest SIFs values for Mode I, Mode II, and Mode III respectively occurred when the a/c ratio was 0.5 and 2.0 of 409.04 MPa√mm and 165.7 MPa√mm respectively. For the value of SIFs r/d, the highest and lowest values occurred at the ratio of 0.12 and 0.05, about 365.57 MPa√mm and 115.25 MPa√mm respectively. This is due to the reduction in the cylindrical cross section of the increased notch radius. Meanwhile for the D/d ratio, the highest and lowest SIFs values occurred at D/d 2.0 and 1.2, about 312.15 MPa√mm and 109.88 MPa√mm respectively. The increase in the value of SIFs was caused by the addition of a large diameter (D), so that the geometry changes became sharper.
Keywords: stress intensity factor, finite element method, singularity, stratified cylinder, cracks. | en_US |
