Thank you Scott! These are great ideas:).Scott said:Bang a long nail part way into a block - then bent it back and forth 'till it breaks.
Bend or twist a plastic part (perhaps a soft drink bottle) back and forth.
Bend a solid wire back and forth - with or without the insulation.
Fatigue failure of material is a type of failure that occurs when a material breaks or fractures under repeated or cyclic loading, even if the stress levels are below the material's ultimate strength. This type of failure is caused by the accumulation of small cracks and damage over time, rather than a single large force.
Fatigue failure can be caused by a variety of factors, including fluctuating or cyclic stresses, poor design or material selection, and manufacturing defects. Environmental factors such as temperature, humidity, and corrosive substances can also contribute to fatigue failure.
To prevent fatigue failure, materials must be designed and selected with consideration for their fatigue strength. Proper maintenance and inspection of materials is also important to identify and repair any potential cracks or damage before they lead to failure. Additionally, reducing or controlling stress levels, avoiding sharp corners or notches, and using surface treatments can help prevent fatigue failure.
Some common signs of fatigue failure include visible cracks or fractures, changes in the material's appearance or texture, and sudden or unexpected failures. In some cases, there may also be audible sounds or vibrations before the material fails.
Fatigue failure is often tested and analyzed using fatigue testing machines, which apply repeated or cyclic loads to a material until it fails. This data is then used to create a stress-life curve, which shows the relationship between applied stress and the number of cycles to failure. Other methods such as finite element analysis and fracture mechanics can also be used to predict and analyze fatigue failure.