BS 7590 standard discusses the method for statistically estimating the volume fraction of phases and constituents by systematic manual point counting with a grid. Grids are a natural extension of this simple order and organization. They help your audience predict where elements and information will be, making both easier to find and navigate.
BS 7590 describes a method for statistically estimating the volume fraction of clearly defined constituents or phases in the microstructure of steel on a metallographically prepared section using a systematic manual point counting technique.
BS 7590 on manual point counting with a grid applies to:
Grids are a natural extension of this simple order and organization. They help your audience predict where elements and information will be, making both easier to find and navigate. Grids are tools for organizing space, text, images, and any other element placed in a design.
BS 7590 provides you with the method which is based on the statistical principle that, when a regular array of points is systematically placed over a two-dimensional section through a uniform microstructure, the proportion of points that fall within a randomly distributed second phase or constituent, designated a-phase, in the structure is equal both to the area fraction of the second phase in a random planar section through the microstructure and to the volume fraction of the second phase.
The method in BS 7590 consists of superimposing a point grid over several different representative fields on the microstructure, counting the number of points included in the constituent or phase, and then calculating the volume fraction of the phase.
BS 7590 provides you with comprehensive guidance useful throughout the process of production.
ISO 9042:1988