Whole Quenching of Small Thin Plate with Low-Power Semiconductor Laser Based on Feed-Speed Combination Problem

A furnace is used in the conventional quenching of small work pieces. When quenching is performed using a furnace, the electricity consumption is high because the heating is performed over a long time period. Moreover, the working environment is unsatisfactory because quenching oils and salt baths are used in the process. Laser quenching has attracted considerable attention as a method for addressing these issues. In previous studies of this method, a laser was used to perform whole quenching on a sheet. However, problems such as deformation and tempering can arise during whole quenching on a thin plate. Furthermore, it is difficult to determine appropriate feed speeds and scanning orders. Therefore, in this paper, we propose a quenching method that uses a semiconductor laser to reduce these thin plate quenching problems. Additionally, an evaluation function is provided for quantitatively assessing the feed speeds. We strive to determine the appropriate laser scanning order from an understanding of decreases in hardness and transformation. We then used the evaluation function to appropriately set the feed speed for the whole quenching of a thin plate using a laser. As a result, we were ultimately able to select a suitable feed speed at which whole quenching can be performed.