原创《纳米非晶态水化硅酸钙接触硬化胶凝性能》：此文是一篇非晶态论文范文,为你的毕业论文写作提供有价值的参考。
摘 要：不同于传统水泥基材料水化硬化特点,本研究旨在探讨纳米非晶态水化硅酸钙（C-S-H）的接触硬化胶凝性能.分别采用了两种不同来源的C-S-H粉体,对其在20～60 MPa压力下恒压3 min进行压制成型,测定成型试件的表观密度和力学性能,并结合成型前后微观结构的变化探讨C-S-H的接触硬化胶凝机理.结果表明,纳米C-S-H具有良好的接触硬化胶凝性能,能在几分钟时间内制备出轻质高强试件.表观密度约为800 kg/m3的试件,其抗压强度可达20～30.5 MPa.微观结构表明,C-S-H颗粒在外力作用下发生粘性流动而使颗粒间距减小至引力范围并发生接触,颗粒的细化和塑性变形促进了结构键的生成,从而使试件具较高强度.
关键词：非晶态；纳米水化硅酸钙；接触硬化；强度；结构键
中图分类号：TU502 文献标志码：A
Research on Contact-hardening Cementitious Properties of Nano-amorphous Calcium Silicate Hydrate
WANG Shuping,PENG Xiaoqin,ZENG Lu
（College of Materials Science and Engineering,Chongqing University,Chongqing 400045,China）
Abstract：Different from the known setting and hardening properties of cementitious materials,this study focuses on the contact-hardening properties of nano- amorphous calcium silicate hydrate （C-S-H）. Two different types of C-S-H powders were used. The powders were compressed under 20～60 MPa for three minutes to produce compacts. Bulk density and compressive strength of the compacts as well as the microstructure of C-S-H before and after compaction were measured.The results show that nano C-S-H presents excellent contact-hardening cementitious properties. Lightweight and high strength compact can be produced by compression in several minutes. When the bulk density of the compact is about 800 kg/m3,compressive strength can be up to 20.0～30.5 MPa. According to the microstructure analysis,the distance of C-S-H particles is reduced during compaction because of the viscoelastic flow. Therefore,the particles become contact to each other,and attractive force between particles is formed. Furthermore,fragmentation and plastic deformation attributes to the compression pressure,leading to the formation of cohesion and adhesion structure. Consequently,the compressive strength of the compacts is greatly improved.
Key words：amorphous； nano calcium silicate hydrate； contact-hardening； strength； bonding
20世紀70年代,部分学者对干燥的水化硅酸钙及水化铝酸钙粉体进行研究,发现这些粉体在一定程度上具有和金属粉末类似的硬化性能,即在压制压力作用下可形成具有一定强度和刚度的硬化试件[1].Feldman和Sereda等[2-3]将完全水化后的水泥浆体进行干燥粉磨并在28.5～143.5 MPa压力下压制成型,制备出具有不同孔隙率的试件.结果表明,试件的强度、孔隙率、密度、吸附性能及弹性模量均受压制压力的影响.此外,研究还指出石膏、碳酸钙及超细石英粉等惰性材料已处于缩聚状态而不能通过压制成型的方法制备试件[1].基于此,Glukhovsky等[1]提出了非稳定矿物质的接触硬化概念：即具有无定型态以及亚稳、亚结晶态的硅酸盐、铝酸盐及铝硅酸盐物质的宏观分散粉体,因拥有较高的自由能,具有和金属粉末相似的性能.这类材料在压制过程中,粒子间极易形成结构键,从而发生硬化.
研究表明,非晶态水化硅酸钙（C-S-H）在纳米尺度和微米尺度的结构和性能和接触硬化性能有着密切的关系.蒲心诚等[4]将水化硅酸钙粉体在300 MPa压力下进行压制成型,仅在120 s内便制备出抗压强度高达84 MPa,具有良好的抗水性的高强石材.彭小芹[5]将含C-S-H的粉体在80 MPa的压制压力下恒压10 min,制备出表观密度仅为1 380 kg/m3的试件,而抗压和抗折强度分别达40.6 MPa和7.6 MPa.彭小芹等[6]对废弃混凝土砂浆组分进行压制成型,结果表明,磨细砂浆组分因含C-S-H而具有一定的接触硬化性能,利用动态水热处理可对这种性能进行优化,所制备的试件表观密度为1 600～1 800 kg/m3,抗压强度和抗折强度分别可达16.8 MPa和5.7 MPa.
非晶态论文参考资料：
结论：纳米非晶态水化硅酸钙接触硬化胶凝性能为适合非晶态论文写作的大学硕士及相关本科毕业论文，相关非晶态合金开题报告范文和学术职称论文参考文献下载。
