Abstract
The change in the grain size distribution during grain growth has been investigated for a commercially-pure titanium. The one- and two-dimensional distributions were measured experimentally. Further, the grain diameter distribution, which is one of the three-dimensional grain size distributions corresponding directly to grain growth, was estimated by the method suggested in the previous paper using the values obtained from the one-dimensional distribution. This method was based on an assumption of the log-normal distribution of the grain diameter (the equivalent volume diameter) D; the distribution of this grain diameter was clearly defined by the geometric mean grain diameter Dg and the standard deviation of lnD or lnσg.
The three-dimensional analysis revealed that the change of the grain diameter distribution of titanium during grain growth was similar to that of its one- or two-dimensional distribution, which is in contrast to the previous result of aluminum. This implies that the increase in Dg with annealing time is analogous to that in the one- or two-dimensional mean grain size; such a tendency was definitly supported by the fact that the standard deviation of logarithm of the grain diameter, lnσg, was almost constant.
