Fabrication of Elbow Pipe by Direct Metal Lamination Using Arc Discharge While Maintaining the Molten Pool in a Horizontal Position

Abstract

Direct fabrication machines have recently been put to practical use for metal products. However, there have been some problems. The devices and usable materials are very expensive, there are limits to the materials, and the strength of the materials is inferior to that of bulk materials, among other problems. The present study aims at the development of a near net shape fabrication machine using an arc discharge that always keeps the molten pool horizontal during the accumula-tion of layers. This is in order to enable the fabrication of an overhanging shape with good accuracy. During the fabrication of the elbow shape, it is necessary to gradually change the torch velocity and the attitude of the molten pool. In this study, we tried to clarify the relationship between torch speed and layer thickness. Finally, the fabricated elbow tube is shown.