TY - JOUR
T1 - Nanoscratch on mechanical properties of interfacial transition zones (ITZs) in fly ash-based geopolymer composites
AU - Li, Wengui
AU - Luo, Zhiyu
AU - Gan, Yixiang
AU - Wang, Kejin
AU - Shah, Surendra P.
N1 - Funding Information:
The authors appreciate the Australian Research Council, Australia (DE150101751; IH200100010; LE210100019), and University of Technology Sydney Research Academic Program at Tech Lab (UTS RAPT).
Publisher Copyright:
© 2021 Elsevier Ltd
PY - 2021/9/29
Y1 - 2021/9/29
N2 - Interfacial transition zones (ITZs) of cementitious concrete are highly heterogeneous, which cause many challenges in accurately obtaining their properties. In this paper, regular aggregates were applied to prepare modelled geopolymer composites, in which ITZs exhibited neat boundaries. Nanoscratch technique with the ability to quickly scan a long distance was adopted to investigate mechanical properties of ITZ and geopolymer paste. To compare the properties of the ITZs and paste, abundant scratch data were analyzed in the form of histograms and Gaussian mixture models. The results showed that the ITZs in geopolymer with silica modulus of 1.5 presented similar properties with the paste, while the ITZs in geopolymer with silica modulus of 1.0 showed significantly higher scratch hardness but lower scratch friction coefficient than paste. Deconvolution analysis revealed that the abnormal hardness and friction coefficient of the paste in geopolymer with silica modulus of 1.0 could be caused by the defects related points. Compared with the traditional scratch scheme, the parallel scratch scheme based on modelled ITZ gave more stable results with a given number of test data, which can provide in-depth information for comparative studies.
AB - Interfacial transition zones (ITZs) of cementitious concrete are highly heterogeneous, which cause many challenges in accurately obtaining their properties. In this paper, regular aggregates were applied to prepare modelled geopolymer composites, in which ITZs exhibited neat boundaries. Nanoscratch technique with the ability to quickly scan a long distance was adopted to investigate mechanical properties of ITZ and geopolymer paste. To compare the properties of the ITZs and paste, abundant scratch data were analyzed in the form of histograms and Gaussian mixture models. The results showed that the ITZs in geopolymer with silica modulus of 1.5 presented similar properties with the paste, while the ITZs in geopolymer with silica modulus of 1.0 showed significantly higher scratch hardness but lower scratch friction coefficient than paste. Deconvolution analysis revealed that the abnormal hardness and friction coefficient of the paste in geopolymer with silica modulus of 1.0 could be caused by the defects related points. Compared with the traditional scratch scheme, the parallel scratch scheme based on modelled ITZ gave more stable results with a given number of test data, which can provide in-depth information for comparative studies.
KW - Deconvolution analysis
KW - Friction coefficient
KW - Geopolymer
KW - Interfacial transition zone (ITZ)
KW - Nanoscratch
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U2 - 10.1016/j.compscitech.2021.109001
DO - 10.1016/j.compscitech.2021.109001
M3 - Article
AN - SCOPUS:85113334723
SN - 0266-3538
VL - 214
JO - Composites Science and Technology
JF - Composites Science and Technology
M1 - 109001
ER -