Search results
Results From The WOW.Com Content Network
Linear elastic fracture mechanics predicts that a crack will extend when the stress intensity factor at the crack tip is greater than the fracture toughness of the material. Therefore, the critical applied stress can also be determined once the stress intensity factor at a crack tip is known.
Concrete fracture analysis is part of fracture mechanics that studies crack propagation and related failure modes in concrete. [17] As it is widely used in construction, fracture analysis and modes of reinforcement are an important part of the study of concrete, and different concretes are characterized in part by their fracture properties. [ 18 ]
If the material breaks on a flat plane, the fracture was brittle, and if the material breaks with jagged edges or shear lips, then the fracture was ductile. Usually, a material does not break in just one way or the other and thus comparing the jagged to flat surface areas of the fracture will give an estimate of the percentage of ductile and ...
CTOD is a single parameter that accommodates crack tip plasticity. It is easy to measure when compared with techniques such as J integral. It is a fracture parameter that has more physical meaning than the rest. However, the equivalence of CTOD and J integral is proven only for non-linear materials, but not for plastic materials.
Fatigue has traditionally been associated with the failure of metal components which led to the term metal fatigue. In the nineteenth century, the sudden failing of metal railway axles was thought to be caused by the metal crystallising because of the brittle appearance of the fracture surface, but this has since been disproved. [ 1 ]
Indeed, fracture or breakdown studies might be the oldest physical science studies, which still remain intriguing and very much alive. Leonardo da Vinci , more than 500 years ago, observed that the tensile strengths of nominally identical specimens of iron wire decrease with increasing length of the wires (see e.g., [ 3 ] for a recent discussion).
Specimen fracture occurs when the stress-intensity-factor range is equal to the applicable threshold-stress-intensity factor for stress-corrosion cracking. When attempting to analyze the effects of corrosion fatigue on crack growth in a particular environment, both corrosion type and fatigue load levels affect crack growth in varying degrees.
Cathodic Protection: Cathodic protection is a technique used to protect metals from corrosion by applying a small electrical current to the metal surface. This technique can also help prevent SCC by reducing the corrosion potential of the metal. [7] Environmental Controls: Controlling the environment around the metal can help prevent SCC.