Electroless Plating Co Based Films for High Performance Magnetic Rotary Encoders

摘要

@@ The recording media are of crucial importance for magnetic rotary encoders of high resolution and accuracy. In the present study, the potential use of electroless plating Co based thin films as the recording media for magnetic encoders was investigated. It was found that the coercivity decreased with increasing film thickness, and reached a maximum of a 570 Oe at the thickness of 300 nm. The results from X-ray photoelectron spectroscopy and transmission electron microscopy indicated that the films have an hexagonal closed-packed structure with c-axis in the plane. The read and write characteristics revealed that the Co based films can be recorded 2048 original magnetic poles while the amplitudes of the output square or sinusoidal waves are uniform. It was suggested that the Co based thin films can be a promising candidate as recording media for high performance magnetic rotary encoders, which may greatly improve the resolution and accuracy of rotational speed or displacement measurements in industrial and automotive applications.