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Fang, W.*; Liu, C.*; Zhang, J.*; 徐 平光; Peng, T.*; Liu, B.*; 諸岡 聡; Yin, F.*
Scripta Materialia, 249, p.116046_1 - 116046_6, 2024/08
The influence of interstitial carbon on the texture evolution of high-entropy alloys during cold rolling was investigated. To prevent carbide formation, elements with weak carbon affinity were carefully selected in the (FeMnCoNi)
C
alloy. Neutron diffraction, electron channeling contrast imaging, and electron backscatter diffraction were used to analyze the texture and microstructure evolution in alloys with and without carbon addition. Though their texture components are similar at the early stage of deformation, the Brass and Goss textures in the carbon-containing alloy at 50% cold rolling reduction are obviously higher than those in the carbon-free alloy, while Copper and S textures are lower. A large number of deformation twins induced in the carbon containing alloy is attributed as the significant reason for the texture differences. This work helps to understand the impact of interstitial carbon on the texture evolution of high-entropy alloys, providing valuable insights for microstructure and performance optimization.
Li, L.*; 宮本 吾郎*; Zhang, Y.*; Li, M.*; 諸岡 聡; 及川 勝成*; 友田 陽*; 古原 忠*
Journal of Materials Science & Technology, 184, p.221 - 234, 2024/06
被引用回数：0 パーセンタイル：0.00(Materials Science, Multidisciplinary)Dynamic transformation (DT) of austenite (
) to ferrite (
) in the hot deformation of various carbon steels was widely investigated. However, the nature of DT remains unclear due to the lack of quantitative analysis of stress partitioning between two phases and the uncertainty of local distribution of substitutional elements at the interface in multi-component carbon steels used in the previous studies. Therefore, in the present study, a binary Fe-Ni alloy with + duplex microstructure in equilibrium was prepared and isothermally compressed in + two-phase region to achieve quantitative analysis of microstructure evolution, stress partitioning and thermodynamics during DT. to DT during isothermal compression and to reverse transformation on isothermal annealing under unloaded condition after deformation were accompanied by Ni partitioning. The lattice strains during thermomechanical processing were obtained via in-situ neutron diffraction measurement, based on which the stress partitioning behavior between and was discussed by using the generalized Hooke's law. A thermodynamic framework for the isothermal deformation in solids was established based on the basic laws of thermodynamics, and it was shown that the total Helmholtz free energy change in the deformable material during the isothermal process should be smaller than the work done to the deformable material. Under the present thermodynamic framework, the microstructure evolution in the isothermal compression of Fe-14Ni alloy was well explained by considering the changes in chemical free energy, plastic and elastic energies and the work done to the material. In addition, the stabilization of the soft phase in Fe-14Ni alloy by deformation was rationalized since the to transformation decreased the total Helmholtz free energy by decreasing the elastic and dislocation energies.
neutron diffraction revealing the achievement of excellent combination of strength and ductility in metastable austenitic steel by grain refinementMao, W.; Gong, W.; Harjo, S.; 諸岡 聡; Gao, S.*; 川崎 卓郎; 辻 伸泰*
Journal of Materials Science & Technology, 176, p.69 - 82, 2024/03
被引用回数：0 パーセンタイル：0.00(Materials Science, Multidisciplinary)Fe-24Ni-0.3C(wt.%)準安定オーステナイト鋼の降伏応力は、平均結晶粒径が35
m(粗粒[CG])から0.5m(超微細粒[UFG])に減少すると3.5倍(158
551MPa)に増加したが、引張伸びは大きく維持された(0.870.82)。結晶粒径が力学特性と変形機構に及ぼす影響を定量的に明らかにするため、室温での引張変形中にCGとUFG Fe-24Ni-0.3C鋼のその場中性子回折測定を行った。CGとUFG試料における塑性変形の初期段階は転位すべりによって支配され、変形後期には変形誘起マルテンサイト変態(DIMT)も生じた。結晶粒の微細化により、DIMTの開始応力が大きく増加し、ひずみに関するDIMTの速度が抑制されることがわかった。結果として、(i)結晶粒微細化によりオー ステナイトが安定化し、DIMTに対して最も安定な結晶粒である
111
//LD(LD:負荷方向)オーステナイト粒でのDIMTの開始が大幅に遅れた。その結果、UFG試験片の111//LDオーステナイト粒のほとんどはマルテンサイトに変態しなかった。(ii)結晶粒の微細化は、マルテンサイト変態の自己促進効果も抑制した。それにもかかわらず、UFG試験片の変態速度が低いDIMTは、CG試験片のより応力を増加させるのに効率がよく、変形中に均一な変形を維持するのに適していた。以上の現象は、UFG準安定オーステナイト鋼の優れた強度と延性の両立に相互に寄与している。
三浦 靖史*; 鈴木 賢治*; 諸岡 聡; 菖蒲 敬久
Quantum Beam Science (Internet), 8(1), p.1_1 - 1_14, 2024/03
Probabilistic fracture mechanics (PFM) is expected as a reasonable structural integrity assessment method for nuclear components such as piping, whose main degradation phenomenon is stress corrosion cracking (SCC). Some input parameters are necessary for PFM analysis, and welding residual stress is one of the most important parameters because welding residual stress affects SCC initiation and propagation. Recently, a double exposure method (DEM) with synchrotron X-ray has been proposed, and the method is an expected candidate for the measurement of welding residual stress with a high spatial resolution. In this paper, the DEM was applied to measure the residual stress of the plate specimen, which was cut from the welded pipe using electrical discharge machining, and detailed stress maps under a plane stress state were obtained. Furthermore, the residual stress distributions of the welded pipe under a triaxial stress state were also evaluated using neutron diffraction. From these results, the method for obtaining a detailed stress map of the welded pipe by the complementary use of high-energy synchrotron radiation X-rays and neutrons was proposed.
興津 貴隆*; 北條 智彦*; 諸岡 聡; 宮本 吾郎*
鉄と鋼, 110(3), p.260 - 267, 2024/02
被引用回数：0 パーセンタイル：0.02We have investigated the dynamic tensile properties of 4, 5, 6-mass%-Mn-containing low carbon steels with multi-phase microstructures containing retained austenite. The five materials used were classified into two groups. The first group of materials, with around 10% of retained austenite, showed normal strain rete dependence of yield strength (YS) and tensile strength (TS) as in conventional high strength steels. The second group of materials, containing 25-36% of retained austenite, exhibited L
ders elongation showed also normal strain rate dependence in YS and flow stress at Lders deformation, but TS varied in a complex manner. Among the second group, in the 4 Mn steel, TS was nearly constant at strain rates below 1 s
but increased slightly at higher strain rates. In the 5 and 6 Mn steels, TS once decreased up to the strain rate of 1 or 10 s, and then began to increase at higher strain rates. These behaviors were discussed in terms of temperature rise during plastic deformation causing suppression of martensitic transformation, and thermal stability of retained austenite. In the 4 Mn steel with relatively unstable retained austenite, almost all the austenite transforms regardless of strain rate. In the 5 and 6 Mn steels, where the retained austenite is moderately stable, strain induced transformation of austenite continues up to high plastic strain, providing a good balance of strength and ductility. At high strain rate, TS decreases slightly due to temperature rise, but at higher strain rates than 1 s, the strain rate sensitivity of flow stress in ferrite become prominent and the flow stress increases.
小山 元道*; 山下 享介*; 諸岡 聡; 澤口 孝宏*; Yang, Z.*; 北條 智彦*; 川崎 卓郎; Harjo, S.
鉄と鋼, 110(3), p.197 - 204, 2024/02
被引用回数：0 パーセンタイル：0.02The local plasticity and associated microstructure evolution in Fe-5Mn-0.1C medium-Mn steel (wt.%) were investigated in this study. Specifically, the micro-deformation mechanism during Lders banding was characterized based on multi-scale electron backscatter diffraction measurements and electron channeling contrast imaging. Similar to other medium-Mn steels, the Fe-5Mn-0.1C steel showed discontinuous macroscopic deformation, preferential plastic deformation in austenite, and deformation-induced martensitic transformation during Lders deformation. Hexagonal close-packed martensite was also observed as an intermediate phase. Furthermore, an in-situ neutron diffraction experiment revealed that the pre-existing body- centered cubic phase, which was mainly ferrite, was a minor deformation path, although ferrite was the major constituent phase.
小山 元道*; 山下 享介*; 諸岡 聡; Yang, Z.*; Varanasi, R. S.*; 北條 智彦*; 川崎 卓郎; Harjo, S.
鉄と鋼, 110(3), p.205 - 216, 2024/02
被引用回数：0 パーセンタイル：0.02 deformation experiments with cold-rolled and intercritically annealed Fe-5Mn-0.1C steel were carried out at ambient temperature to characterize the deformation heterogeneity during Lders band propagation. Deformation band formation, which is a precursor phenomenon of Lders band propagation, occurred even in the macroscopically elastic deformation stage. The deformation bands in the Lders front grew from both the side edges to the center of the specimen. After macroscopic yielding, the thin deformation bands grew via band branching, thickening, multiple band initiation, and their coalescence, the behavior of which was heterogeneous. Thick deformation bands formed irregularly in front of the region where the thin deformation bands were densified. The thin deformation bands were not further densified when the spacing of the bands was below 
10 m. Instead, the regions between the deformation bands showed a homogeneous plasticity evolution. The growth of the thin deformation bands was discontinuous, which may be due to the presence of ferrite groups in the propagation path of the deformation bands. Based on these observations, a model for discontinuous Lders band propagation has been proposed.
Kim, G.*; Cho, S.-M.*; Im, S.*; Suh, H.*; 諸岡 聡; 菖蒲 敬久; 兼松 学*; 町田 晃彦*; Bae, S.*
Construction and Building Materials, 411, p.134529_1 - 134529_18, 2024/01
This study explores the influence of the interatomic structure of sodium aluminosilicate hydrate (N-A-S-H) with varying silica contents on the mechanical properties of metakaolin-based geopolymer. Geopolymer pastes comprising Si/Al ratios between 2.0 and 3.0 were synthesized. A larger number of Si-O-Si linkages compared to Si-O-Al linkages and a higher atomic number density were found in the geopolymers with higher silica contents, which enhanced the compressive strength of the geopolymer pastes up to the optimal Si/Al ratio of 2.5. The paste with a Si/Al = 2.5 exhibited a greater portion of Q
(1Al and 2Al) and denser morphology compared to the other geopolymer pastes. Furthermore, in-situ high-energy synchrotron X-ray scattering experiments were conducted to assess the elastic modulus of the aluminosilicate structure at a local atomic scale. The modulus value in real space decreases with increasing silica contents up to Si/Al = 2.5 and increases with the presence of excessive unreacted silica fume. The modulus value in reciprocal space for the axial and lateral directions both presented a positive value at the geopolymer comprising a Si/Al ratio higher than 2.5, indicating that the load-bearing property of N-A-S-H changed at higher Si/Al ratios. Moreover, the smallest difference between the strains along the axial and lateral directions was detected for the geopolymer with Si/Al = 2.5 in both the real and reciprocal space, owing to the most interconnected and flexible nanostructure, which led to the highest mechanical strength.
Zhang, Y.*; 丸澤 賢人*; 工藤 航平*; 諸岡 聡; Harjo, S.; 宮本 吾郎*; 古原 忠*
ISIJ International, 64(2), p.245 - 256, 2024/01
被引用回数：0 パーセンタイル：0.02As-quenched martensite in carbon steels needs to be tempered to restore its ductility and toughness for practical applications. During tempering of martensite, microstructural evolutions induced by a series of reactions relevant to carbon diffusion is known to occur. In this study, multi-aspect characterization using advanced techniques such as in-situ neutron diffraction, transmission electron microscopy and three-dimensional atom probe tomography, was performed to investigate the changes in tetragonality, physical properties, microstructure and solute carbon content in high-carbon martensite, with an aim to clarify its low-temperature tempering behaviors. A binary alloy with a chemical composition of Fe-0.78 mass%C was austenitized and quenched to prepare the as-quenched martensite, followed by tempering in continuous heating at different heating rates. It was found that various reactions occurred sequentially during tempering, starting from the structure modulation generated by carbon clustering in the 0th stage, then followed by the precipitation of metastable 
-carbide particles on linear features in the 1st stage, towards the later decomposition of retained austenite and precipitation of cementite in the 2nd and 3rd stages, respectively. After analyzing the experimental results, the solute carbon content in martensite tempered under various conditions was found to be in good agreement with that estimated from the lattice volume expansion, whereas the evaluation based on the tetragonality might lead to some underestimation of the solute carbon content in martensite tempered at high temperatures.
neutron diffraction during cryogenic cooling山下 享介*; Harjo, S.; 川崎 卓郎; 諸岡 聡; Gong, W.; 藤井 英俊*; 友田 陽*
ISIJ International, 64(2), p.192 - 201, 2024/01
被引用回数：0 パーセンタイル：0.02 neutron diffraction measurements were performed on Fe-33Ni-0.004C alloy (33Ni alloy) and Fe-27Ni-0.5C alloy (27Ni-0.5C alloy) during cooling from room temperature to the cryogenic temperature (4 K) to evaluate changes in the lattice constants of austenite and martensite, and changes in the tetragonality of martensite due to thermally induced martensitic transformation. As the martensitic transformation progressed, the lattice constants of austenite in both alloys deviated to smaller values than those predicted considering the thermal shrinkage, accompanied by an increase in the full width at half maximum of austenite. The fresh martensite formed in both alloys had a body-centered tetragonal (BCT) structure, regardless of the carbon content. The tetragonality of martensite decreased with progressive martensitic transformation during cooling in the 33Ni alloy, but was almost constant in the 27Ni-0.5C alloy. This suggests that carbon is necessary to maintain the tetragonality of martensite during cooling. The tetragonality of martensite in the 27Ni-0.5C alloy decreased during room temperature aging because of carbon mobility.
Cho, S.*; Suh, H.*; Im, S.*; Kim, G.*; 兼松 学*; 諸岡 聡; 町田 晃彦*; 菖蒲 敬久; Bae, S.*
Construction and Building Materials, 409, p.133866_1 - 133866_20, 2023/12
The effects of various initial carbonation curing environments on the phase evolution and resulting mechanical characteristics of tricalcium silicate paste were studied. For the analyses of the reaction products and microstructure, synchrotron X-ray diffraction, thermogravimetry, Fourier transform-infrared spectroscopy, scanning electron microscopy with energy dispersive X-ray spectroscopy and high-resolution X-ray computed tomography were utilized. C
S cured under carbonation environment pressurized by 0.1 MPa showed excellent mechanical properties owing to the highest degree of reaction and homogeneous generation of CaCO with low-Ca/Si calcium silicate hydrates, resulting in a dense matrix with refined pore structure. CS paste treated under other carbonation conditions underwent deteriorative microstructural phase transitions, including void evolution by decalcification of C-S-H and an inhomogeneous composition of crystalline phases, resulting in inferior properties.
Wang, Q.*; Ma, N.*; Huang, W.*; Shi, J.*; Luo, X.-T.*; 冨高 宙*; 諸岡 聡; 渡邊 誠*
Materials Research Letters (Internet), 11(9), p.742 - 748, 2023/09
Cold spray (CS) has emerged as a representative of solid-state additive manufacturing (AM) via supersonic impact. It enables a high deposition rate of solid-state microparticles. Delamination, however, tends to occur when depositing too thick; this remains to be conquered. Here, a CS-like process, warm spray (WS), was presented. Interestingly, it was found that the appropriate increase in particle temperature can effectively reduce the residual stress amplitude, relieving the concentrated tensile stress and safeguarding the additively manufactured components from interfacial delamination even when depositing too thick. The key role of temperature on delamination was identified in solid-state AM via supersonic impact.
neutron diffractionGong, W.; Harjo, S.; 友田 陽*; 諸岡 聡; 川崎 卓郎; 柴田 曉伸*; 辻 伸泰*
Acta Materialia, 250, p.118860_1 - 118860_16, 2023/05
被引用回数：6 パーセンタイル：92.77(Materials Science, Multidisciplinary)Martensitic transformation is accompanied by the generation of microscale and macroscale internal stresses during cooling below the martensitic transformation start temperature. These internal stresses have been determined through X-ray or neutron diffraction, but the reported results are not consistent, probably because the measured lattice parameter is influenced not only by the internal stress but also by several factors, including solute elements and crystal defects. Therefore, neutron diffraction combined with dilatometry measurements during martensitic transformation and subsequent cyclic tempering were performed for an Fe-18Ni alloy. The phase strains calculated by lattice parameter variations show that a hydrostatic compressive strain in austenite and a tensile strain in martensite arose as the martensitic transformation progressed during continuous cooling or isothermal holding. However, the phase stresses of austenite and martensite estimated from these strains failed to hold stress balance law when dense crystal defects involved in the processes. After these crystal defects were removed by appropriate tempering, the stress balance law held well. Meanwhile, the phase stresses of austenite and martensite were changed to opposite, revealing their true identity. Various crystal defects in austenite and martensite, introduced by plastic accommodation, were suggested to affect their lattice parameters and then their phase stresses.
安江 歩夢*; 川上 真由*; 小林 謙祐*; Kim, J.; 宮津 裕次*; 西尾 悠平*; 向井 智久*; 諸岡 聡; 兼松 学*
Quantum Beam Science (Internet), 7(2), p.15_1 - 15_14, 2023/05
Neutron diffraction is a noncontact method that can measure the rebar strain inside concrete. In this method, rebar strain and stress are calculated using the diffraction profile of neutrons irradiated during a specific time period. In general, measurement accuracy improves with the length of the measurement time. However, in previous studies, the measurement time was determined empirically, which makes the accuracy and reliability of the measurement results unclear. In this study, the relationship between the measurement time and the measurement standard deviation was examined for reinforced concrete specimens under different conditions. The aim was to clarify the accuracy of the measurement of rebar stress using the neutron diffraction method. It was found that if the optical setup of the neutron diffractometer and the conditions of the specimen are the same, there is a unique relationship between the diffraction intensity and the rebar stress standard deviation. Furthermore, using this unique relationship, this paper proposes a method for determining the measurement time from the allowable accuracy of the rebar stress, which ensures the accuracy of the neutron diffraction method.
鈴木 賢治*; 三浦 靖史*; 城 鮎美*; 豊川 秀訓*; 佐治 超爾*; 菖蒲 敬久; 諸岡 聡
材料, 72(4), p.316 - 323, 2023/04
Residual stresses in small-bore butt-welded pipe of austenitic stainless steel have never been measured. It is difficult to obtain a detailed residual stress map of the root welded part, because the gauge volume in neutron diffraction is large. The stress evaluation of the welded part by synchrotron X-rays was also difficult due to the dendritic structure. In this study, a double exposure method (DEM) with high-energy synchrotron X-rays was applied to measuring the details of the residual stress of the welded part, and we succeeded in obtaining the detailed axial and radius stress maps of the root welded part of the plate cut from the welded pipe, though the stress map was under the plane stress condition. The hoop stress map of the butt-welded pipe was obtained using the strain scanning method with neutrons under the triaxial stress state. The axial and radius stress maps under triaxial stress state were made up using the complementary use of the synchrotron X-ray and neutron. As a result, the detailed stress maps of the root welded part of the butt-welded pipe were obtained. The obtained map sufficiently explained the initiation and propagation of SCC.
synchrotron X-ray scattering and nanoindentation testIm, S.*; Jee, H.*; Suh, H.*; 兼松 学*; 諸岡 聡; Choe, H.*; 西尾 悠平*; 町田 晃彦*; Kim, J.*; Lim, S.*; et al.
Construction and Building Materials, 365, p.130034_1 - 130034_18, 2023/02
被引用回数：6 パーセンタイル：65.14(Construction & Building Technology)Nanocrystalline calcium-silicate-hydrate (C-S-H) is a typical heterogeneous material with a multiscale structure spanning a wide length scale from angstrom to micrometer, and whose structure is determined by the Ca/Si ratio. In this study, we directly applied compressive loads on synthetic C-S-H pastes with Ca/Si ratios of 0.6-1.2 and investigated their mechanical properties using the elastic modulus calculated at three length scale levels (i.e., angstrom to nanometer, micrometer, and millimeter) via in-situ synchrotron X-ray scattering, nanoindentation tests, and strain gauges, respectively. Further, 
Si nuclear magnetic resonance spectroscopy was conducted on the C-S-H pastes to elucidate the alterations in the silicate polymerization. The experimental results confirmed the deformation behavior of the C-S-H paste with different Ca/Si ratios under external loading, which was demonstrated to be transferred from the surface of the pastes to particles owing to the presence of multiscale pores.
ders band propagation in an Fe-5Mn-0.1C medium Mn steel clarified through scanning electron microscopy小山 元道*; 山下 享介*; 諸岡 聡; Yang, Z.*; Varanasi, R. S.*; 北條 智彦*; 川崎 卓郎; Harjo, S.
ISIJ International, 62(10), p.2043 - 2053, 2022/10
被引用回数：7 パーセンタイル：72.10(Metallurgy & Metallurgical Engineering) deformation experiments with cold-rolled and intercritically annealed Fe-5Mn-0.1C steel were carried out at ambient temperature to characterize the deformation heterogeneity during Lders band propagation. Deformation band formation, which is a precursor phenomenon of Lders band propagation, occurred even in the macroscopically elastic deformation stage. The deformation bands in the Lders front grew from both the side edges to the center of the specimen. After macroscopic yielding, the thin deformation bands grew via band branching, thickening, multiple band initiation, and their coalescence, the behavior of which was heterogeneous. Thick deformation bands formed irregularly in front of the region where the thin deformation bands were densified. The thin deformation bands were not further densified when the spacing of the bands was below 10 m. Instead, the regions between the deformation bands showed a homogeneous plasticity evolution. The growth of the thin deformation bands was discontinuous, which may be due to the presence of ferrite groups in the propagation path of the deformation bands. Based on these observations, a model for discontinuous Lders band propagation has been proposed.
ders deformation in an Fe-5Mn-0.1C medium-Mn steel小山 元道*; 山下 享介*; 諸岡 聡; 澤口 孝宏*; Yang, Z.*; 北條 智彦*; 川崎 卓郎; Harjo, S.
ISIJ International, 62(10), p.2036 - 2042, 2022/10
被引用回数：11 パーセンタイル：85.65(Metallurgy & Metallurgical Engineering)The local plasticity and associated microstructure evolution in Fe-5Mn-0.1C medium-Mn steel (wt.%) were investigated in this study. Specifically, the micro-deformation mechanism during Lders banding was characterized based on multi-scale electron backscatter diffraction measurements and electron channeling contrast imaging. Similar to other medium-Mn steels, the Fe-5Mn-0.1C steel showed discontinuous macroscopic deformation, preferential plastic deformation in austenite, and deformation-induced martensitic transformation during Lders deformation. Hexagonal close-packed martensite was also observed as an intermediate phase. Furthermore, an in-situ neutron diffraction experiment revealed that the pre-existing body-centered cubic phase, which was mainly ferrite, was a minor deformation path, although ferrite was the major constituent phase.
Harjo, S.; Gong, W.; 川崎 卓郎; 諸岡 聡; 山下 享介*
ISIJ International, 62(10), p.1990 - 1999, 2022/10
被引用回数：1 パーセンタイル：14.88(Metallurgy & Metallurgical Engineering)Two mechanisms inconsistent each other, a relaxation of type II internal stress and a presence of mobile dislocation, were previously proposed to describe the low elastic limit of as-quenched lath martensite steels. In this study, neutron diffraction experiments were performed to revisit the deformation behavior of lath martensite steel. The highly dense random arrangement dislocations easily moved at the beginning of deformation, then accumulated, annihilated and changed the arrangement differently depending on the orientation of the packet with respect to the deformation direction. The movement of highly dense random arrangement dislocations played an important role as a mechanism at the beginning of deformation, and can be a true feature of mobile dislocations.
Kim, G.*; Im, S.*; Jee, H.*; Suh, H.*; Cho, S.*; 兼松 学*; 諸岡 聡; 小山 拓*; 西尾 悠平*; 町田 晃彦*; et al.
Cement and Concrete Research, 159, p.106869_1 - 106869_17, 2022/09
被引用回数：18 パーセンタイル：91.81(Construction & Building Technology)This study explored the effect of M-S-H formation on the local atomic arrangements and mechanical properties of C-S-H. The elastic moduli of the samples were calculated using shifted atomic distances (r) and d-spacings (d) acquired by applying an external load on the pastes during X-ray scattering experiments. The experimental results indicated that the crystal structure of C-S-H remained intact with MgCl
addition. At the highest Mg/Si ratio (Ca/Si = 0.6, Mg/Si = 0.2), change in the dominant phase occurred from C-S-H to M-S-H because the low pH environment hindered the formation of C-S-H and facilitated the formation of M-S-H. The elastic modulus decreased with increasing Mg/Si ratio up to 0.1 owing to both C-S-H destabilization and low M-S-H content in the samples. Conversely, the elastic modulus increased in the paste synthesized with the highest Mg/Si ratio because considerable M-S-H had formed, which exhibited a higher elastic modulus than C-S-H.
