The microstructures near to 211 phase clusters within samples were studied by means of transmission electron microscopy. The results indicated that the crystal defects around 211 phases were closely related to the distance between 211 particles, d211. The twin spacing increased with decreasing d211. At the same time, the thickness of the twin boundary decreased. When d211 was less than 0.51, there were almost no defects between the 211 particles.

L.Li, Z.Zhang, D.Jin: Journal of Materials Science, 1995, 30[4], 879-82