一、前言许多研究者和技术人员所进行的淬火材料非破坏性评价方法的研究,最近取得了显著的进展。其中一部分是利用热电动势和电阻变化的方法,大多则利用涡流和磁化的方法。笔者试图利用能应用于生产线上而且比较简便的非接触式测量的涡流法,研制非破坏式测定表面淬火材料内部硬度分布的装置。特别是高频淬火材料,需要精密地测量 I. INTRODUCTION Recent research on the nondestructive evaluation of quenched materials by many researchers and technicians has made significant progress recently. One part is the use of thermoelectromotive force and resistance changes in the way, most of the use of eddy current and magnetization methods. The author tried to use the production line can be relatively simple and non-contact measurement of eddy current method to develop non-destructive determination of the surface hardness of the quenching material distribution device. In particular, high-frequency quenching materials, the need for precision measurement