一、前言基准磁平是校准带和磁带电磁特性测试的一项最重要的标准,这对磁记录工作者来说是不言而喻的。五十年代起一些工业化国家即先后建立起以直流置换法定标的基准磁平标准,如BASF(IEC)、AGFA(D1N)、EMI、J1S、BTS等均以直流置换 I. INTRODUCTION Benchmark Magnet Flatness is one of the most important criteria for the calibration of magnetic tapes and the magnetic properties of tapes, which is self-evident to magnetic recording practitioners. Since the 1950s, some industrialized countries have set up benchmark standards such as BASF (IEC), AGFA (D1N), EMI, J1S, BTS and so on, all of which have been replaced by DC