The invention discloses a
laser additive manufacturing method and a
laser additive manufacturing device of
metal parts. In the
laser additive manufacturing method, a layered-manufactured profile-followed cylinder is used as a forming cylinder, namely before each
metal part layer is manufactured, a layer of closed
thin wall is manufactured, the formed cavity is used as the profile-followed cavity, the height of the profile-followed cavity is the same as that of the
metal part layer to be manufactured, and the shape of the profile-followed cavity is adapted to that of the metal part layer to be manufactured, so as to provide a plane reference and a cavity for laying
powder; the layered-manufactured profile-followed cylinder is used, a scanning
galvanometer is used for performing
selective laser melting and forming, the metal part
layers are manufactured layer by layer,
layers of the profile-followed cavities are finally stacked to form the profile-followed cylinder, and the
layers of metal parts are stacked to form metal parts. The
laser additive manufacturing device comprises a laser
galvanometer melting and forming device and a
thin wall preparation device which alternatively work, so as to accomplish the
selective laser melting and forming process. The method and the device keep the advantages of the
selective laser melting (SLM) metal additive
manufacturing technology, uses the profile-followed cylinder to break the limit of the conventional SLM device fixed-size forming cylinder, and thus achieving the high-precision manufacture of the large-size even over-sized parts.