Abstract
In order to understand the behavior of scale deformation on hot-rolling, the characteristic of not only scale itself but also the interface between scale and material is important.
For this reason, the following experimental methods were developed for measuring the quantitative strength of the interface. At first, after generating scale on the two pillar specimens at high temperature, the scale/scale interface between these was joined by pressurizing at high temperature. Next, by the tensile test of the joined specimen, the force and the stroke curve were obtained. In this experiment, there are some peaks on the force and the stroke curve by exfoliations of scale/scale and scale/material. To estimate the exfoliation stress, the exfoliated area of each interface was evaluated from the curve.
By using this technique, the influence that a condition of the pressure or the interface roughness gave to exfoliation stress was studied. As a result, it was found that the exfoliation stress between a scale/material was affected by the joining stress. In addition, it was found that exfoliation stress becomes greater, with the rougher interface surface between a scale/material.
