用纳米压痕复合扫描电子显微镜分析水泥砂浆中单一组相的力学性能(英文)

Nanomechanical Properties of Individual Phases in Cement Mortar Analyzed Using Nanoindentation Coupled with Scanning Electron Microscopy

采用纳米压痕复合扫描电子显微镜研究了硬化水泥砂浆的物相和对应的微观力学性能。结果发现:微观尺度上,砂子、未水化水泥颗粒和氢氧化钙的弹性模量分别为105.55、107.06 GPa和60.88 GPa。同时,低密度水化产物和高密度水化产物的存在得到了验证,其弹性模量的统计分析值分别为18.42GPa和32.53GPa。从测试结果的对比分析可以看出,未水化水泥颗粒弹性模量的测试值与文献值基本保持一致,氢氧化钙弹性模量的测试值高于文献值;水化产物弹性模量统计分析的结果虽与文献保持一致,但超高密度水化产物的存在仍有不确定性。

A commonly used hardened cement mortar was analyzed via the grid-nanoindentation coupled with scanning electron mi- croscope image analysis. In the microscopic scale, the elastic modulus of sand, unhydrated cement particles and portlandite are 105.55, 107.06 GP and 60.88 GPa, respectively. The co-existence of low density hydration products and high density hydration products was found, and their calculated elastic moduli were 18.42 GPa and 32.53 GPa, respectively. The results show that the testing value ofun- hydrated cement particle is similar to the published value, while the testing value of portlandite is much higher than the published value. The results also reveal that the statistical values of hydration products are in accord with the published values, however, the existence of ultra-high density hydration products is still an assumption.