Materials
·
2023
·Vol. 16
·期 13
·4549
·
IF 3.4
Chuiyuan Kong,Bin Zhou,Rongxin Guo,Feng Yan,Rui Wang,Changxi Tang
Based on the physical and chemical properties of red sandstone (RS), RS is used to produce composite cementitious materials. The flowability, mechanical strength, and micromechanics of a red sandstone–cement binary cementitious material (RS-OPC) were investigated as functions of the amount of RS replacing the cement (OPC). Additionally, the feasibility of producing red sandstone–phosphogypsum–cement composite materials (RS-PG-OPC) using the phosphogypsum (PG)- enhanced volcanic ash activity of RS was investigated. The products of hydration and microstructures of RS-OPC and RS-PG-OPC were analyzed by XRD, FTIR, TG-DTG, and SEM. RS enhanced the flowability of RS-OPC relative to the unmodified cement slurry but lowered its mechanical strength, according to the experiments. When the quantity of OPC replaced was greater than 25%, the compressive strength after 28 days was substantially reduced, with a maximum reduction of 78.8% (RS-60). The microscopic mechanism of RS-OPC suggested that the active SiO2in the RS can react with Ca(OH)2to produce C-S-H but can only utilize small quantities of Ca(OH)2, confirming the low volcanic ash activity of RS. RS was responsible for dilution and filling. The incorporation of 5% PG into RS-PG-OPC slowed the hydration process compared with RS-OPC without PG but also increased the flowability and aided in the later development of the mechanical strength. This was primarily because the addition of PG provided the system with sufficient Ca2+and SO42−to react with [Al(OH)6]3−to form ettringite (AFt), therefore accelerating the dissolution of Al3+in RS to generate more AFt and C-(A)-S-H gels. To some extent, this excites the volcanic ash of RS. Therefore, if there is an abundance of waste RS in the region and a lack of other auxiliary cementitious materials, a sufficient quantity of PG and a finely powdered waste RS component can be used to replace cementitious materials prepared with OPC to reduce the mining of raw OPC materials.Keywords:red sandstone;phosphogypsum;flowability;mechanical strength;micromechanics;volcanic ash activity
研究领域:
建筑材料学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
·
2017
·
IF 4.873
Hao-hao Ren,Dong-xia Xu,Guang-ming Yan,Gang Zhang,Xiao-jun Wang,Sheng-ru Long,Jie Yang
The aim of this study was synthesis of the polyphenylene sulfide (PPS) containing carboxyl unit and investigation of the effect of modified PPS used as compatibilizer on the interfacial micromechanical properties of carbon fiber (CF) reinforced PPS composites. A series of copoly(1,4-phenylene sulfide)-poly(2,5-phenylene sulfide acid) (PPS-COOH)s containing different proportions of carboxyl units in the side chain were synthesized by the reaction of dihalogenated monomer and sodium sulfide via nucleophilic substitution polymerization under high pressure. According to the results of FT-IR, DSC , TGA , mechanical test and contact angle test , all of the copolymers were found to have analogous structure and improved hydrophilic property comparing with neat PPS. There was a good physical compatibility between the modified PPS and the pure PPS. The microbond test (measuring apparent interfacial shear strength (τ app ) of the composite) and scanning electron microscopy (SEM) also showed that the optimized PPS-COOH (7.5) can be used to improve the micro-mechanical properties and interfacial bonding between CF and PPS matrix. The maximum τ app of 10%PPS-COOH (7.5)/PPS/CF composite was 49.1 MPa, which had increased 36.0% comparing with that of the pure PPS/CF composite (36.1 MPa).
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER COMPOSITES
·
2024
·Vol. 45
·期 10
·9196-9208
·
IF 4.8
Ningmin Duan,Yong Li,Zhenyu Shi,Jilai Wang,Chengpeng Zhang,Xuefeng Tang,Guilong Wang
Nowadays, it is still a huge challenge to predict the interlaminar shear strength (ILSS) of three-phase carbon fiber reinforced polymer (CFRP). Herein, the three-phase micromechanical model is innovatively constructed to predict the ILSS of CFRP, and the conception of new matrix is proposed by establishing a connection between the third phase and the matrix, which effectively solves the problem of uneven distribution of the third phase. To verify the accuracy of the micromechanical model, the Ti 3 C 2 T x MXene/CFf/epoxy composites were fabricated by the co-blending, layer-by-layer assembly and hot-pressing technology, and the finite element simulation analysis was also performed based on the micromechanical model. The results show that the micromechanical model possesses high accuracy. Specifically, the experimental value of ILSS of the composite with 1 wt% Ti 3 C 2 T x MXene content is 52.12 MPa, and the errors of simulation value (56.64 MPa) and theoretical prediction value (58.69 MPa) are 8.67% and 12.61% MPa, respectively. Besides, the detailed fracture mechanism of the composite is presented based on the fracture morphology and simulation results. It is believed that this work will provide more possibilities for the prediction of the interlaminar shear performance of three-phase composites. Highlights A novel micromechanical model is used to predict the ILSS of three-phase composite. The accuracy of the micromechanical model is verified by simulation and experiment. The main failure form of the Ti 3 C 2 T x MXene/CFf/epoxy composite is matrix broken. The micromechanical model of the three-phase composites has high accuracy.
研究领域:
材料科学
·
复合材料工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Mingyuan Yan,Xudong Cheng,Lunlun Gong,Zhiyi Lun,Pan He,Long Shi,Chenjie Liu,Yuelei Pan
Owing to excellent high temperature resistance, high porosity and light weight, SiC aerogels possess great application prospects in thermal insulation and adsorption. However, poor mechanical properties of SiC aerogels, such as brittleness and non-bendability, hinder its application; it is still a challenge to improve and regulate the mechanical properties of SiC aerogels. Here, for the first time, we propose a micromechanical design strategy to prepare flexible SiC nanowire/mullite fiber composite aerogels (SMCAs). By optimizing the aspect ratio of the skeleton fibers to regulate the stress state of microstructures, the maximum compressive stress of that SMCAs could bear can be tuned systematically from 1.2 kPa to 1254.8 kPa, spanning 3 orders of magnitude. More importantly, thanks to its micromechanical design, SMCAs can withstand up to 80% compression deformation and up to 90° bending deformation. The present work provides a new idea for the regulation of mechanical properties of ceramic aerogels.
研究领域:
材料科学
·
机械工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）