【摘 要】
：
Calcium sulfate hemihydrate whiskers were synthesized successfully via one-step hydrothermal crystallization method using phosphogypsum at 130 °C for 240 min with an initial slurry mass fraction of 2.5wt％. The phase compositions, microstructures, thermal
【机 构】
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School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyan
【出 处】
：
武汉理工大学学报（材料科学版）（英文版）
论文部分内容阅读
Calcium sulfate hemihydrate whiskers were synthesized successfully via one-step hydrothermal crystallization method using phosphogypsum at 130 °C for 240 min with an initial slurry mass fraction of 2.5wt％. The phase compositions, microstructures, thermal properties and molecular structures of as-prepared samples were analyzed by XRD, ESEM, EDS, TG-DTA, and FT-IR. The influence of raw materials\' ball-milling time on the morphologies of whiskers was investigated. The effects of impurities on crystallization morphologies and length to diameter ratio (L/D) of calcium sulfate hemihydrate whiskers were studied. The results indicated that the calcium sulfate dihydrate crystalline could be translated directly into fibrous calcium sulfate hemihydrate whiskers. It was beneficial to form fine fiber structure when the ball-milling time of the raw material was 15 min. Aspect ratio of calcium sulfate hemihydrate whiskers decreased with increasing content of impurities. Moreover, the relative growth mechanism of whisker crystals via one-step hydrothermal crystallization method was discussed in detail.
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