METHOD OF DETERMINING CAUSE OF DEFECTS ON STEEL MATERIAL SURFACE

摘要

A pulse laser beam is focused to irradiate areas including defects on the surface of a steel material. The energy density of the pulse laser beam on the steel surface is limited to the range of 10 kW/mm<2> to 100 MW/mm<2>. The pulse laser beam is moved in a zigzag in a region including defects to evaporate the steel material and form fine steel particles, which are collected for continuous analysis so as to detect the cause of the defects occurring on the steel material.