In injection molding of thermosetting resins, resin burrs may be deposited on the mold surface resulting in product defects. Therefore, it is necessary to remove these resin burrs at high speed. In this study, we investigated the delamination of resin burrs from the mold surface using an excimer laser, which can emit a relatively high-energy pulse beam, leading to large-area processing. Unlike conventional methods, delamination could be achieved with an area on the order of millimeters with a single pulse of laser irradiation. The fluence of the laser beam, the thickness of the resin burr, and the surface roughness of the mold were identified as factors affecting delamination performance. Finally, delamination was shown to be caused by outgassing from the resin when the temperature increased, thermal expansion and contraction of the resin burrs, and laser ablation.

It is important to improve the machined surface or sub-surface quality of metals. This study was performed to develop a cutting technique capable of generating a localized compressive hydrostatic stress field around the cutting point to suppress excess plastic flow and improve the machined surface quality. A cutting tool equipped with a sliding jig to locally generate a compressive hydrostatic stress field around the cutting point was developed. Cutting experiments with pure aluminum were conducted, and the results were compared to conventional cutting. The results showed that the localized hydrostatic pressure-assisted cutting reduced plastic deformation, such as burr formation. To theoretically verify the effectiveness of the developed method, molecular dynamics simulations were also conducted. The results confirmed that the developed method was effective for reducing excess plastic deformation, such as burr formation, during cutting by applying localized hydrostatic pressure.