Biao Li^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.25, No.1, pp. 1-2, 2023, DOI:10.32604/icces.2023.09818

Abstract High-temperature coatings are extensively used in aircraft engines and industrial gas turbines to protect hot-section components from harsh operating environments [1]. Representative high-temperature coatings include thermal barrier coatings and environmental barrier coatings, which are applied to substrates made of superalloy and ceramic matrix composites, respectively. The durability of the coatings is of significant importance for the structural integrity of the components [2-4]. A segmented microstructure was widely used to improve the coatings' durability. A network of through-thickness vertical cracks is introduced into the outer layer of the coatings, which increases the compliance of the coatings… More >

Xin Wang^1,3, Ying Yan^1,3, Hongmei Ji^1,3,*, Xiaowu Li^1,2,*

Journal of Renewable Materials, Vol.11, No.8, pp. 3297-3308, 2023, DOI:10.32604/jrm.2023.027066

Abstract As an essential renewable mineral resource, mollusk shells can be used as handicrafts, building materials, adsorbents, etc. However, there are few reports on the wear resistance of their structures. The Vicker’s hardness and friction, and wear resistance of different microstructures in mollusk shells were comparatively studied in the present work. The hardness of prismatic structures is lower than that of cross-lamellar and nacreous structures. However, the experimental results of sliding tests indicate that the prismatic structure exhibits the best anti-wear ability compared with foliated, crossed-lamellar, and nacreous structures. The anti-wear and hardness do not present More > Graphic Abstract

Liang Yu^1,2,3, Yuan Liu^1,2,3, Xiuling Cao^4,*, Yulong Yan^1,2,3, Chen Zhang^1,2,3, Yanli Jiang^1,2,3,*

Journal of Renewable Materials, Vol.11, No.7, pp. 3057-3072, 2023, DOI:10.32604/jrm.2023.025732

Abstract In this study, the effect of sintering temperature and the addition of kaolin, a sintering agent, on the microscopic, phase, and mechanical properties of ceramics were investigated using secondary aluminum dross (SAD) as the main component in the manufacturing of ceramics. The basic phases of the ceramics were Al₂O₃, MgAl₂O₄, NaAl₁₁O₁₇, and SiO₂ without the addition of kaolin. The diffraction peaks of MgAl₂O₄, NaAl₁₁O₁₇, and SiO₂ kept decreasing while those of Al₂O₃ kept increasing with an increase in temperature. In addition, the increase in temperature promoted the growth of the grains. The grains were uniform in size and regular… More > Graphic Abstract

Jing Yu¹, Jie Ren², Guangming Shen³, Weixiang Sun², Hui Wang^4,*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.9, pp. 2385-2398, 2023, DOI:10.32604/fdmp.2023.027877

Abstract In this paper, the influence of NaCl freeze-thaw (F-T) cycles and dry-wet (D-W) alternations on the flexural, compressive and bonding strengths of alkali-activated fly ash (FA) and a blast furnace slag powder (BFS) is investigated. The considered NaCl concentration is 3%. The effect of polypropylene fibers on the mechanical strengths is also examined. Scanning electron microscopy (SEM), thermogravimetry (TG) and X-ray diffraction (XRD) are selected to discern the mechanisms underpinning the NaCl-induced erosion. The obtained results indicate that the best results in terms of material resistance are obtained with admixtures containing 60% BFS and 40%… More >

Jinfa Jiang¹, Long Xiong², Ming Bao², Zihan Zhou^2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.8, pp. 1983-1995, 2023, DOI:10.32604/fdmp.2023.026023

Abstract Reasonable treatment and utilization of waste residuals discharged during the production of ready-mixed concrete is an important problem in the cement industry. In this study, a composite admixture was prepared by using ready-mixed concrete waste residuals, furnace slag, and water granulated slag. The grinding characteristics of such material were investigated. Moreover, the effect of such admixture on cement hydration and pore structure was analyzed by X-ray diffraction, thermogravimetric-differential scanning calorimetry, scanning electron microcopy and mercury intrusion porosimetry. As shown by the results: The grinding characteristics of the waste residuals can be improved significantly by mixing More > Graphic Abstract

Yonggan Yang^1,2,3,4, Zihao Kang¹, Binggen Zhan^1,3,*, Peng Gao^1,3,*, Qijun Yu¹, Yanlai Xiong⁴, Jingfeng Wang^1,3, Yunsheng Zhang⁵

Journal of Renewable Materials, Vol.11, No.4, pp. 1895-1910, 2023, DOI:10.32604/jrm.2023.025059

Abstract In this paper, the effects of different mineral admixtures and sulfate solution types on the appearance, mass change rate, relative dynamic elastic modulus, and corrosion resistance coefficient of concrete were systematically studied. X-ray Diffraction (XRD), Mercury Intrusion Porosimetry (MIP), Scanning Electron Microscopy (SEM), and X-ray Computed Tomography (X-CT) were used to explore and analyze the changes in the microstructure and the corrosion products of concrete in the sulfate solution. The results show that the existence of magnesium ions accelerates concrete deterioration. There is a critical dosage of fly ash for magnesium sulfate resistance of concrete.… More > Graphic Abstract

Zhihai He^1,2, Menglu Shen¹, Jinyan Shi^3,*, Jingyu Chang¹, Víctor Revilla-Cuesta⁴, Osman Gencel⁵

Journal of Renewable Materials, Vol.11, No.4, pp. 1835-1852, 2023, DOI:10.32604/jrm.2023.024887

Abstract Recycling solid waste in cement-based materials cannot only ease its load on the natural environment but also reduce the carbon emissions of building materials. This study aims to investigate the effect of recycled glass powder (RGP) on the early-age mechanical properties and autogenous shrinkage of cement pastes, where cement is replaced by 10%, 20% and 30% of RGP. In addition, the microstructure and nano-mechanical properties of cement paste with different RGP content and water to binder (W/B) ratio were also evaluated using SEM, MIP and nanoindentation techniques. The results indicate that the early-age autogenous shrinkage… More > Graphic Abstract

Mengqi Cong^*, Yang Zhang, Yunlong Zhang, Xiao Liu, Yalin Lu, Xiaoping Li

Journal of Renewable Materials, Vol.11, No.4, pp. 1977-1989, 2023, DOI:10.32604/jrm.2023.023849

Abstract Magnesium alloy has been considered as one of the third-generation biomaterials for the regeneration and support of functional bone tissue. As a regeneration implant material with great potential applications, in-situ Mg₂Si phase reinforced Mg-6Zn cast alloy was comprehensively studied and expected to possess excellent mechanical properties via the refining and modifying of Mg₂Si reinforcements. The present study demonstrates that the primary and eutectic Mg₂Si phase can be greatly modified by the yttrium (Y) addition. The size of the primary Mg₂Si phases can be reduced to ~20 μm with an addition of 0.5 wt.% Y. This phenomenon is… More > Graphic Abstract

Wei Chen^1,*, Weijie Shan¹, Yue Liang¹, Frederic Skoczylas²

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.3, pp. 679-696, 2023, DOI:10.32604/fdmp.2022.021249

Abstract This study deals with the analysis of the detrimental effects of a “sulfate attack” on cement mortar for different dry-wet cycles. The mass loss, tensile strength, and gas permeability coefficient were determined and analyzed under different exposure conditions. At the same time, nitrogen adsorption (NAD), scanning electron microscopy (SEM), and X-ray diffraction (XRD) techniques were used to analyze the corresponding variations in the microstructure and the corrosion products. The results show that certain properties of the cement mortar evolve differently according to the durations of the dry-wet cycles and that some damage is caused to More >

Zhiqiang Wu^1,2, Yi Wu², Renjun Xie², Jin Yang¹, Shujie Liu³, Qiao Deng^4,*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.2, pp. 399-406, 2023, DOI:10.32604/fdmp.2022.020402

Abstract One of the main obstacles hindering the exploitation of high-temperature and high-pressure oil and gas is the sealing integrity of the cement sheath. Analyzing the microstructure of the cement sheath is therefore an important task. In this study, the microstructure of the cement sheath is determined using a CT scanner under different temperature and pressure conditions. The results suggest that the major cause of micro-cracks in the cement is the increase in the casing pressure. When the micro-cracks accumulate to a certain extent, the overall structure of the cement sheath is weakened, resulting in gas More >