随着磁头磁盘间有效距离的不断降低，磁头可能以飞行、冲浪和滑行三种状态工作，为了使磁头能够稳定工作，必须实时监测和识别磁头所处的状态。提出一种利用摩擦电流来实时监测磁头工作状态的方法。利用空气轴承电动机、热飞高控制磁头、功率加载控制单元、静电计、加载/卸载单元、静电屏蔽箱等组建了摩擦电流的测试系统。通过每隔0.1 V逐步给飞高控制磁头加载电压的方式，改变磁头磁盘间的距离，测量了不同磁头磁盘间距时的摩擦电流，得出了区分三种工作状态的摩擦电流区间。当摩擦电流值在10-4μA以下时，磁头工作在稳定的飞行状态；当摩擦电流值在6～50 μA时，磁头工作在冲浪状态；当摩擦电流值在140 μA以上时，磁头工作在滑行状态。
With the gradual decrease of the effective clearance between the hard disk and the magnetic head, the head may work at three states-flying, surfing and sliding. In order to make the head stable working, the state of the head must be monitored and identified. A method is given to real-time monitor the state of the head by measuring the tribocurrent resulting from the friction between the disk and the head. A tribocurrent measurement system is constructed which includes air bearing motor, thermal-flight-height-control head, power loading control unit, electrometer, loading/unloading unit, electrostatic shielding box and so on. By applying the voltage to the thermal-flight-height-control head with the step of 0.1 V, the clearance between the hard disk and the head is gradually decreased, and the tribocurrent at different clearance was measured by the electrometer, and the current range of distinguishing three working states of the head is obtained. When the tribocurrent is below 10-4 μA, the head works stably at the flying state. When the tribocurrent is at 6 μA-50 μA, it works at the surfing state. When the tribocurrent is more than 140 μA, it works at the sliding state.
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