NON-GAUSSIAN SURFACE-ROUGHNESS DISTRIBUTION OF MAGNETIC MEDIA FOR MINIMUM FRICTION STICTION/

Contact of two rough surfaces at an interface occurs at a small fracti on of the nominal area. The real area of contact and interfacial adhes ion primarily control the friction of an interface. With the presence of a thin film of liquid lubricant or adsorbed water layer al the inte rface, menisci form around the contacting and near-contacting asperiti es. The meniscus formation results in stiction problems in the head-me dium interfaces. The objective of this research is to predict optimum surface roughness for minimum friction/stiction. For the first time, t he effects of skewness and kurtosis of surfaces with non-Gaussian dist ribution on contact area and meniscus contribution have been studied. A numerical model that accounts for the effects of roughness distribut ion and liquid film was used for this study. Based on this study a sur face with non-Gaussian distribution with positive skewness between 0 a nd 0.2 and/or with high values of kurtosis (K greater than or equal to 5) should be used for low friction and stiction. (C) 1996 American In stitute of Physics.