Metrology

Surface profile of a highly finished surface

Primary aim of secondary manufacturing processes is to obtain products having better surface quality, high dimensional accuracy and close tolerance. Such processes include machining or metal cutting operations (like turning, milling, drilling, reaming, precision turning, grinding, lapping, honing, AJM, USM, EDM, LBM, IBM, etc.) and surface modification operations (like heat treatment, coloring, coating, etc.). Each of these processes has varying level of capabilities in terms of surface quality and precision.

Surface integrity (SI) data set by Field et al. (1972)

Functional performance of any solid surface relies on the physical conditions and chemical composition of the concerned surface and subsurface layers. Quality is defined as fit for intended purpose. Similarly, quality of a solid surface is one subjective matter and its assessment primarily depends on intended functionalities. Let us explain the same with examples. With respect to decorative artefact, appearance of the surface has importance rather than presence of micro-cracks