高性能粉煤灰蒸压砖的研究  

Research on High-performance Fly Ash Autoclaved Bricks

作　　者：任强[1] 郭鹏飞 海鸥 REN Qiang;GUO Pengfei;HAI Ou(College of Materials Science and Engineering,Shaanxi University of Science&Technology,Xi’an 710021,China)

机构地区：[1]陕西科技大学材料科学与工程学院,西安710021

出　　处：《中国陶瓷》2023年第1期56-62,共7页China Ceramics

基　　金：陕西省自然科学基础研究计划(2019JQ-785)。

摘　　要：以粉煤灰和生石灰为原料,蒸压法制备高性能粉煤灰蒸压砖,利用XRD、SEM等手段研究了制备工艺条件对蒸压砖的物相组成、微观结构及其性能的影响。结果表明:在蒸压砖成型前对“粉煤灰-生石灰-水”混合坯料采用保湿加热消化技术,能够生成大量的Ca1.5SiO3.5·xH2O等微晶,这些微晶在之后的蒸压过程中能够促进水化反应的进行,生成更多的Ca1.5SiO3.5·xH2O等水化物晶体,明显提高其力学性能、抗冻性能等关键性能指标。在最佳条件下,蒸压砖的平均抗压强度和抗折强度分别达到36.71 MPa和8.0 MPa,远超国家行业最高标准MU30的30 MPa和4.8 MPa,35次冻融循环后的(D35)质量和强度损失率分别为0.67%和8.32%,远优于行业标准的5%和15%。Using fly ash and quicklime as raw materials,high-performance fly ash autoclaved bricks were prepared by autoclaving,and the influence of preparation process conditions on the phase composition,microstructure and properties of autoclaved bricks was studied by XRD,SEM and other means.The results show that the moisturizing heating and digestion technology of"fly ash-quicklime-water"mixed blank before autoclaved brick forming can generate a large number of Ca1.5SiO3.5·xH2O and other microcrystals.These microcrystals can promote the hydration reaction in the subsequent autoclaving process,generate more hydrated crystals such as Ca1.5SiO3.5·xH2O,and significantly improve their mechanical properties,frost resistance and other key performance indicators.Under the best conditions,the average compressive strength and flexural strength of autoclaved bricks reach 36.71 MPa and 8.0 MPa,respectively,far exceeding the30 MPa and 4.8 MPa of MU30,the highest standard in the national industry.The mass and strength loss rates of D35 after 35 freeze-thaw cycles were 0.67%and 8.32%,respectively,far better than the industry standard of 5%and 15%.

关 键 词：粉煤灰 消化温度 水化反应 力学性能 抗冻性能 

分 类 号：TQ174.764[化学工程—陶瓷工业]