The invention provides a method for achieving
laser bending
metal plate forming through a pre-stretch-bending method. Resilience can be reduced to a large extent, and then the bending angle of a plateis increased. The method comprises the steps that firstly, a formed workpiece is fixed to a three-dimensional
numerical control platform, one end of the workpiece is fixed through a clamp, and a stretch bending device firstly applies longitudinal tension and then applies
transverse pressure to the other free end of the workpiece; and then the upper surface of the plate is heated in a scanned modeby using
laser, finally, after the hating area of the plate is completely cooled, the stretch bending device is removed, and the
transverse pressure and the longitudinal tension are relieved. A largenumber of literatures prove that the stress state inside the plate can be changed under
bending force, more tangential
pressure stress generated on the inner side of a neutral layer of the
laser heated area is converted into tensile stress, the whole cross section of the plate is under the action of the tensile stress in the tangential direction, and after relieving, resilience of inner-layer fibers and outer-layer fibers counteract each other so that the resilience can be greatly reduced, and then the bending angle of the plate is increased; and the method is suitable for forming of high-
hardness, high-
brittleness and difficult-to-deform and medium-thickness plate materials, and has a great application prospect in the fields of
aerospace,
medical treatment and automobile manufacturing.