Determination of the WC grain size in hardmetals using stereology – A critical analysis

Stereology is frequently applied to determine mean grain size and grain size distribution of the carbide phase in hardmetals. The spreading use of softwares based in stereological routines tends to intensify this practice. Nevertheless, the utilization of stereology must be done with criticism. This paper examines the use of both the intercept length and the cross section area to represent grain size. Moreover, it proposes the use of the section perimeter to do the same representation. The limitation of the mean intercept length to represent the mean grain size of a population of grains with different sizes is discussed. The intercept length distribution does not represent the true population of grains in the structure since part of the grains is excluded from the measurement.