Surface finish refers to acceptable levels of roughness in polymeric or metal-mechanic components. Whenever two machine surfaces come into contact with one another, the quality of the surface finishing plays an important role in their performance and wear, reports Anand Bewoor in "Metrology & Measurement." Factors affecting surface finish include cutting tools and machinery, the method used to cut the component, and the material's temperature.
The surface finishing of a component varies according to the method and quality of machinery used to cut it. Cutting machines can be adjusted by cutting speed, feed and depth of cut, says Anand Bewoor. To avoid an over-rough surface, these variables are adjusted according to the type of material being cut as well as the size of the component being made.
Method of Cutting
Traditionally, cutting tools and machines have metal blades. However, the use of lasers and high-pressure water has become a popular alternative to traditional mechanical methods of cutting. The new methods produce better overall results, including smoother surface finishes. Laser cutting has many advantages over traditional methods, including higher cutting precision and lower surface roughness. A water jet cutter also has its advantages, offering higher-performance surface-finishing in small-size components.
Temperature affects the volume of most materials. Metals start to expand when the temperature increases, while polymers can be deformed. Therefore, the temperature of a material being cut can affect the surface finish of a component. Especially when using mechanical methods, temperatures higher than each material's optimum for the cutting process often result in uneven surfaces and increased surface roughness, says Anand Bewoor.