MEASUREMENT OF HEAD WEAR RATES USING CUSTOM HIGH-SENSITIVITY ELECTRICAL ELEMENTS

A technique for measuring the wear rate of a tape recording head is de scribed that can produce a theoretical dimensional resolution of 0.02 nm. Custom four wire elements are located in the gap of the actual rec ording head design to be tested (rather than using substitutes) and ca n be strategically placed to measure the wear rate across the width of the tape. Temperature compensation is achieved by measurement of a sp are identical element in the head structure set back from the wear sur face such that it does not receive wear. The wear rate at various loca tions across the head gap lines of NiZn ferrite heads have thus been o btained continuously as a function of the amount of CrO2 tape passed a nd show that the wear rate is greater near The tape edges. Due to the high sensitivity of the test elements, use of long reels of tape and p lacement of multiple heads in the same tape path, comparisons of head contour shape and/or materials can be made in a very short test time.