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通过SEM显微技术，从亚微观结构研究Na5P3O10对Ca(OH)2碳化反应中CaCO3结晶的控制生长过程.结果表明，CaCO3结晶的成核、生长在时间上是重叠的伴随过程.在CaCO3反应结晶的起始阶段，Na5P3O10的存在促进了CaCO3的大量成核.通过SEM可以观测到大量亚稳态CaCO3籽晶(R=23～26nm)的存在.这时，CaCO3晶体生长并不符合Zener-Ham理论的扩散生长规律.结晶生长由穿越晶体界面的短程扩散控制.在反应结晶末期，SEM已观测不到亚稳态CaCO3籽晶的存在.CaCO3结晶生长遵循长程扩散控制模型R(t)=λi(Dt)n，时间指数n=0.4874～0.4992(理论值n=0.5).随着碳化液中Na5P3O10浓度的增大，常数λiDn由16.69降低至11.36，从而有效地控制CaCO3的结晶生长.

The ultrafine CaCO3 crystal growth controlled by Na5P3O10 in the carbonation of Ca(OH)2 suspension,was investigated by using SEM. The results show that CaCO3 nucleates along with the nucleus growth. The presence of Na5P3O10 accelerates the CaCO3 nucleation. At the initial stage,a large number of CaCO3 nucleus engender,and metastable tiny crystallites (R=2326nm) can be observed in SEM imagine. The CaCO3 crystal growth controlled by short distance diffusion when mass pass through the crystal interface,does not correspond to Zener-Ham theory. At the next stage,the metastable tiny crystallites disappear in SEM imagine. The CaCO3 crystal growth abides by the long distance control model R(t)=λi(Dt)n,in which the time coefficient n is 0.4874～0.4992 (theory value n=0.5) and the constant λiDn decreases from 16.69 to 11.36. Consequently,Na5P3O10 can effectively inhabit the CaCO3 crystal growth.