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Surface finish and surface roughness are the same concept, and surface finish is another term for surface roughness.

Surface finish is proposed according to the human visual point of view, while surface roughness is proposed according to the actual microscopic geometry of the surface. Because in line with international standards (ISO), China used surface roughness and abolished surface finish after the 1980s. After the promulgation of the national standard of surface roughness GB3505-83 and GB1031-83, surface finish is no longer used.

There is a corresponding comparison table between surface finish and surface roughness (see the following figure). Roughness has a measured formula, and the finish can only be compared with the template gauge. So roughness is more scientific than finish.