The invention discloses a method and device for forming a
metal reducer pipe based on a
laser shock wave technology and belongs to the technical field of
laser processing. In the invention, the upper end part, separated from a
pipe fitting, of a plugging rod is coated with a
laser energy absorption layer; a laser beam enters the interior of a
pipe billet to be formed along the axis of the pipe billet, thereby irradiating on the
absorption layer on the upper end part of the plugging rod; the
absorption layer absorbs laser energy so as to be gasified and ionized, thus forming high-
voltage plasmas; and the high-
voltage plasmas quickly expand to form a high-amplitude
shock wave, thereby promoting the expansion of the pipe billet until the pipe billet is jointed with the profile of a mould, therefore the deformed shape of the pipe billet is in accordance with the profile of the mould. In the invention, the laser
shock wave controlled in parameter is utilized as a power source for internal
high pressure forming of the pipe billet, and good safety is provided; and the method and device provided by the invention are suitable for not only forming the pipe billet of a material extremely low in
yield limit, but also forming the pipe billet with high yield strength; besides, continuous multi-pulse laser
irradiation can be performed and uninterrupted multi-
impact can be carried out; and high production efficiency is ensured.