Tasopintaisuutta
Tasopintaisuutta is a term used in Finnish to describe the quality of a surface to be planar. It refers to how closely a surface conforms to an ideal plane, minimizing deviations in the direction perpendicular to that plane. In metrology and engineering, flatness is a form tolerance that is independent of orientation; it is measured as the maximum deviation of points on the surface from a theoretical plane or as the distance between two parallel reference planes containing the surface. In practice, flatness is commonly specified as a numeric tolerance, for example a tolerance of 0.05 mm means all points must lie within a 0.05 mm-thick zone between two parallel planes.
Measurement methods include surface plates, dial indicators, coordinate measuring machines (CMM), profilometers, and optical methods. The
Causes of non-flatness include machining errors, thermal distortion, residual stresses, warping during cooling, and deformation from
To improve tasopintaisuutta, processes include a consistent machining sequence, proper fixturing, temperature control, stress-relief treatments, and
Etymology: the Finnish word tasopintaisuutta derives from taso (plane) and pinta (surface) with the suffix -aisuus