Inspection of Surface Rolled Sintered Gears using Eddy-Current Sensor

Abstract

A inspection regarding surface rolled sintered gears performed in-line is required. The authors have proposed a inspection method using an eddy-current sensor. Since this method uses the eddy-current, a inspection of gears is possible in a nondestructive manner with a short time. In this paper, in order to perform a inspection using an eddy-current sensor, porosity, residual stress, resistivity, and relative permeability of the surface rolled sintered steel are measured. Furthermore, output voltage characteristics of surface rolled sintered gears that the amounts of surface rolling differ are measured. As a result, it is clarified that porosity and resistivity decrease and relative permeability increase with increasing residual stress. Moreover, it is clarified that over surface rolled gear can be judged with output voltage.