What is a seam fatigue test?

A seam fatigue test is a type of mechanical test that is used to evaluate the strength and durability of a seam in a material, such as a welded or stitched joint. Seams are often critical locations in a material where stress concentrations can occur, making them more susceptible to failure or damage over time. A seam fatigue test is designed to simulate the cyclic loading and unloading that a seam may experience during its service life, and to measure the number of cycles that the seam can withstand before failure.

There are several different types of seam fatigue tests, but one of the most common is the rotating bending fatigue test. In this test, a test specimen with a seam is clamped at both ends and subjected to cyclic bending loads while being rotated at a constant speed. The bending loads cause the seam to undergo cyclic tension and compression, and the number of cycles required to cause failure is recorded.

Another type of seam fatigue test is the tensile fatigue test, in which a test specimen is subjected to cyclic tensile loads along the length of the seam. The number of cycles required to cause failure is again recorded.

Seam fatigue tests are commonly used in industries such as aerospace, automotive, and civil engineering to evaluate the durability of welded or stitched joints in materials such as metals, plastics, and composites. The results of these tests can be used to optimize the design of seams and to select materials and manufacturing processes that will improve the overall strength and durability of the seam.