Description |
According to available experimental data on tensile fracture tests for metals, the magnitude of fracture toughness is generally dependent on specimen geometry, applied stress, and testing temperature. Fracture toughness, the measure of the plastic work required to resist fracture, is used mainly for structural design applications. Knowing how the fracture toughness varies with different parameters helps improve design by fabricating more reliable and more durable structures. With fracture toughness experimental data the dependence on geometry, stress and temperature is expressed in to a function to predict fracture. This dependence is approximated by a semi-empirical relationship, based on both experimental data and fracture theory. Results are presented for several metals divided into aluminum, steel, and titanium subgroups for a varied range of specimen geometry including width, thickness and crack size, and yield stress. Additional results are presented to account for the effect of temperature. Furthermore, data of a few specimens for a given material are used to corroborate that the relationship is valid for the whole range of fracture toughness values for the same material. Results show that this relationship is capable of predicting the behavior of fracture toughness accounting for the diverse effects, within an approximation error. The results provide clear evidence of the dramatic impact the relationship can have if it is used for design, instead of performing costly and time consuming experiments. |