A predictive analysis for optimum contour-after-wear for magnetic heads

Reliable reproduction of recorded signals is dependent upon a good head-tape interface, and particularly, upon adequate contact pressure at the gap. In the case of grooved magnetic heads the pressure profiles are complex 3-dimensional surfaces. The head contours, as machined, may cause pressure profiles which are unfavorable to good signal reproduction. A mathematical analysis is outlined, which forecasts the progressively changing head contours and pressure profiles in terms of the average depth of head wear due to passage of tape (magnetic or lapping tape). The analysis indicates the amount of wear needed to substantially improve the pressure profile. Good correlation is shown between the theoretical predictions and actual test values.