 HomeNewsThe difference between surface finish and roughness

The difference between surface finish and roughness

2022-06-09

Surface finish and roughness are the same concept . Ningbo Tianhui is a professioal factory which can meet your requiremnets.

Surface finish is another name for roughness. The smoothness is proposed according to the human visual point of view; and the roughness is proposed according to the actual microscopic geometry of the surface. In order to be in line with international ISO standards, China adopted surface roughness after the 1980s, and abolished surface finish.

cnc machining

After the promulgation of the national standard for surface roughness, the surface finish is no longer used. Roughness has a calculation formula for measurement, and smoothness can only be compared with a sample gauge, so roughness is more scientific and rigorous than smoothness. Surface roughness refers to the unevenness of the small spacing and small peaks and valleys existing on the machined surface. The distance between its two peaks or two valleys is very small, which belongs to the error of microscopic geometry. The smaller the surface roughness, the smoother the surface. Surface roughness is generally formed by the processing method employed and other factors. Surface roughness affects wear resistance, fit stability, fatigue strength, corrosion resistance, sealing, contact stiffness, and measurement accuracy. Mechanical drawings are generally marked with Ra to represent. For more information ,please be kindly to contact us .

Previous: the difference between forging and casting

Next: CNC Turning and Milling: Do You Understand the Difference Between Them?