【摘要】 为实现湿基α-半水石膏制备高强石膏制品，研究了湿基α-半水石膏陈化时间、粉磨时间、浇筑料浆温度及缓凝剂掺量等工艺参数对高强石膏凝结时间和强度的影响，并确定最佳制备工艺。此外，采用X射线衍射、扫描电子显微镜等微观测试手段，揭示了各因素对强度的影响机理。结果表明：陈化时间越长，石膏凝结时间越短，制品强度越低；随着粉磨时间延长，石膏凝结时间显著缩短，制品强度先升高后降低；料浆温度越高，石膏凝结时间越长，制品强度越低。最佳制备工艺：陈化时间5 min、粉磨时间20 s、料浆温度20℃。在此基础上加入0.08%(质量分数)缓凝剂能够有效地延长石膏凝结时间并提高硬化强度，制备的石膏制品性能优异，绝干抗折强度为14.1 MPa,绝干抗压强度为58.3 MPa。微观测试结果表明，各工艺参数会通过改变石膏标稠用水量和水化进程来影响石膏内部结构的密实程度和二水石膏晶体的生长发育，最终影响制品硬化强度。更多还原

【Abstract】 In order to produce high strength gypsum products from wet-base α-hemihydrous gypsum, the ideal preparation method was identified by analyzing the effects of aging time, grinding time, molding temperature and retarder content on setting time and strength of high strength gypsum. Additionally, scanning electron microscopy and X-ray diffraction were used to clarify how each aspect affected strength. The results show that longer aging period results in lower strength and shorter setting duration of gypsum. As the grinding time prolongs, the setting time of gypsum significantly shortens, and the strength of product increases first and then decreases. The higher the slurry temperature is, the longer the gypsum setting time is, and the lower the product strength is. The optimal preparation process is aging time of 5 min, grinding time of 20 s, and slurry temperature of 20 ℃. On this basis, adding 0.08%(mass fraction) retarder can effectively prolong the setting time of gypsum and improve the hardening strength. The prepared gypsum products have excellent performance, with a drying flexural strength of 14.1 MPa and a drying compressive strength of 58.3 MPa. The microscopic test results indicate that various process parameters can affect the compactness of the internal structure of gypsum and the growth and development of dihydrate gypsum crystals by changing the water content and hydration process of gypsum, ultimately affecting the hardening strength of product.更多还原