Influences of field conditions on the rupturing instability of a circular thin magnetic film

Ching-Yao Chen - L.--W. Lo

Department of Mechanical Engineering, National Yunlin University of Science and Technology, Yunlin, Taiwan, Republic of China }

Abstract
We report the experimental observations of four modes of striking film rupturing instabilities. Formations of different modes are found to depend strongly on the initial circular diameters and field conditions, such as the field strengths and field increasing rates. Three modes of well-ordered rupturing patterns and a very disordered fourth mode instability are identified. Under a constant field strength, a more unstable mode is triggered at a larger diameter of the circular film. In addition to the strong dependence on the initial diameters, we also confirm that a more unstable mode occurs in the field condition with either a stronger magnetic field or a higher field increasing rate, as commonly expected. Figs 5, Refs 26.