For the preparation of metallographic specimens, the traditional viewpoint emphasizes on obtaining a bright surface without wear marks, while the modern viewpoint emphasizes the effective removal of the deformation damage layer on the surface of the specimens. Only in this way can the true structure of the specimens be observed under the microscope. Secondly, attention should be paid to improving the sample preparation efficiency and reducing costs. The traditional metallographic sample preparation steps include cutting, mosaic, grinding into a plane, polishing and polishing. The first two belong to the preparation steps of sample preparation, and the last three belong to the main steps of sample preparation.