Fretting analysis of tin-coated terminals under rotational motion

In most cases, studies on the fretting phenomena on connector terminals have been conducted using equipment with a reciprocal linear motion base. Actually, the basic movement of connectors is linear sliding. However, the actual movement of connectors during use includes a rotational element of movement, especially in the case of vibration-driven fretting. Experiments based on rotational motion are difficult in the case of small-sized terminals. The rotation center and embossed part must be aligned to precisely the correct position. The desired accuracy is approximately 10 micrometers, while regular industrial products include the cumulative errors. The sizes of outlines, the position of embossed, thermal expansion, and measurement errors are typical causes. The authors have constructed a testing apparatus based on rotational motion and proposed an algorithm for computational analysis. Finally, the differences in results between linear and rotational motion are discussed.