摘要
在富镁镍渣(HMNS)中掺入偏高岭土(MK)制备了富镁镍渣基地质聚合物,通过高温实验探究了富镁镍渣基地质聚合物的耐高温性能,并采用XRD、FT-IR、SEM和同步热分析(TG-DSC)等表征分析了富镁镍渣基地质聚合物的水化产物、相变和显微结构.结果表明,富镁镍渣基地质聚合物在室温下的抗压强度可达16.0 MPa.暴露于1200 ℃后,抗压强度提高至38.8 MPa且热膨胀率仅为1.05％,表现出优异的耐高温性能.室温下主要的结晶产物是镁磷石和柏林石.非晶相主要由—Al—O—P—、—Si—O—P—、—Si—O—P—O—Al—和—P—O—Mg—等结构组成.暴露于高温后,相变、物理自由水的蒸发、化学结合水的脱水、去羟基化、胶凝相的收缩以及烧结是影响富镁镍渣基地质聚合物力学性能和微观结构变化的主要因素.
Abstract
This work prepared a high-magnesium slag(HMNS)-metakaolin(MK)based geopolymer by incorporating MK into HMNS.High temperature resistance property of the high-magnesium nickel slag based geopolymer was studied and microscopic characterization techniques such as X-ray diffraction(XRD),Fourier-transform infrared spectroscopy(FT-IR),scanning electron microscopy(SEM),and synchronous thermal analysis(TG-DSC)were employed to analyze the changes of hydration products,phase transitions,and microstructure changes of the high-magnesium nickel slag based geopolymer.Results show that the compressive strength of the high-magnesium nickel slag based geopolymer can reach 16.0 MPa at room temperature.After exposure to 1200℃,the compressive strength increased to 38.8 MPa with a thermal expansion coefficient of only 1.05％,demonstrating excellent high-temperature resistance.At room temperature,the primary crystalline products are newberyite and berlinite.The amorphous phase mainly consists of structures such as—Al—O—P—,—Si—O—P—,—Si—O—P—O—Al—,and—P—O—Mg—.After exposure to high temperatures,phase transitions,evaporation of physically bound water,dehydration of chemically bound water,dehydroxylation,shrinkage of the gel phase,and sintering are the main factors influencing the mechanical properties and microstructural changes of high-magnesium nickel slag based geopolymer.
基金项目
国家自然科学基金项目(51974168)
内蒙古自治区科技重大专项(2019ZD023)
内蒙古自治区科技重大专项(2021ZD0028)
硅酸盐建筑材料国家重点实验室(武汉理工大学)开放基金资助项目(SYSJJ2020-08)
维普
万方数据