Abstract: The effects of calcined phosphogypsum on the hydration process of the autoclaved silicate products were investigated in this paper.The influence of adding phosphogypsum calcined at different temperatures on the hydration rate of autoclaved silicate products was analyzed for un-reacted Ca(OH)₂ content and combined water.The hydrates were determined with XRD and SEM.It was found that the hydration of autoclaved silicate products with added phosphogypsum calcined over 500℃ was greatly improved.The hydrates of the autoclaved silicate products with added phosphogypsum calcined over 500℃ had more un-reacted Ca(OH)₂ content and combined water in the same curing time, and the research indicated that adding phosphogypsum calcined over 500℃ could also reinforce the compressive strength of autoclaved silicate products.It was pointed out that the aluminate phase present in the raw materials cannot hydrate to form more ettringite during autoclaved curing, and rapid formation of such hydrates as calcium silicate hydrate (1) and tobermorite with a more compact structure is the main reason for strengthening autoclaved silicate products.

Key words: calcined phosphogypsum, autoclaved silicate products, hydrates, hydration rate

摘要： 磷石膏经高温煅烧改性后与粉煤灰、砂粉、石灰及水泥熟料等制备蒸压硅酸盐制品，研究了不同温度煅烧的磷石膏对蒸压硅酸盐制品水化过程的影响，用蒸压制品中未反应的Ca(OH)₂量及结合水量分析它们的反应速率，用XRD测定蒸压硅酸盐制品的水化产物，并结合SEM分析，结果表明，经煅烧的磷石膏对蒸压硅酸盐制品的水化有明显的促进作用，托勃莫来石与C-S-H(1)等水化产物的迅速生长而形成密实的水化产物结构是其增强蒸压硅酸盐制品的根本原因。

关键词: 煅烧磷石膏, 蒸压硅酸盐制品, 水化产物, 水化速度