| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an exhaust pipe for automobile such as an exhaust manifold capable of demonstrating the desired characteristic by executing the welding without any trouble such as burn-through even for a member having a flange part wrinkled by the pressing, at low cost. <P>SOLUTION: After pressing two stainless steel plates to respectively predetermined shapes, flange parts of worked parts are superposed, and superposed parts are subjected to the laser beam welding to manufacture an exhaust pipe for automobile. The laser beam welding is executed two times, including a first laser beam welding in which the laser beam is applied in a defocus state with the focal point not being on, at a part with a space, an upper plate on the laser beam application side is melted and recessed to the lower plate side to reduce the space, and at a part without any space, the upper and lower plates are welded in a non-penetrating manner to the back side of the lower plate, and subsequently, a second laser beam welding in which the laser beam is applied in a penetrating manner to the back side of the lower plate. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
