Xueli He^1,, Shengkun Lv^1,, Ruifeng Dou^1,*, Yanying Zhang¹, Junsheng Wang², Xunliang Liu¹, Zhi Wen¹

CMC-Computers, Materials & Continua, Vol.80, No.2, pp. 2873-2895, 2024, DOI:10.32604/cmc.2024.052571 - 15 August 2024

Abstract Four typical theories on the formation of thermal tears: strength, liquid film, intergranular bridging, and solidification shrinkage compensation theories. From these theories, a number of criteria have been derived for predicting the formation of thermal cracks, such as the stress-based Niyama, Clyne, and RDG (Rapaz-Dreiser-Grimaud) criteria. In this paper, a mathematical model of horizontal centrifugal casting was established, and numerical simulation analysis was conducted for the centrifugal casting process of cylindrical Al-Cu alloy castings to investigate the effect of the centrifugal casting process conditions on the microstructure and hot tearing sensitivity of alloy castings by… More >

Ping Xu^1,*, Zhiwei Zhang¹, Zhenguo Hou^2,3, Mankui Zheng¹, Jin Tong¹

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.6, pp. 1299-1312, 2024, DOI:10.32604/fdmp.2023.046183 - 27 June 2024

Abstract In this paper, cement and dechlorinated Polyaluminum Chloride Residue (PACR) have been used to prepare a net slurry and mortar specimens. Two hydration activity indicators have been used to quantitatively analyze the dechlorinated PACR hydration activity. In particular, the effect of dechlorinated PACR content on the compressive strength of mortar has been assessed by means of compressive strength tests. Moreover, X-ray diffraction (XRD) and scanning electron microscopy (SEM) have been employed to observe the microstructure of the considered hydration products. The following results have been obtained. The 28th day activity index of the dechlorinated PACR… More >

Yehao Long, Jing Zhong^*, Tongdi Zhang, Li Chen, Lijun Zhang^*

CMC-Computers, Materials & Continua, Vol.79, No.3, pp. 3435-3453, 2024, DOI:10.32604/cmc.2024.051629 - 20 June 2024

Abstract Physical Vapor Deposited (PVD) TiAlN coatings are extensively utilized as protective layers for cutting tools, renowned for their excellent comprehensive performance. To optimize quality control of TiAlN coatings for cutting tools, a multi-scale simulation approach is proposed that encompasses the microstructure evolution of coatings considering the entire preparation and service lifecycle of PVD TiAlN coatings. This scheme employs phase-field simulation to capture the essential microstructure of the PVD-prepared TiAlN coatings. Moreover, cutting simulation is used to determine the service temperature experienced during cutting processes at varying rates. Cahn-Hilliard modeling is finally utilized to consume the More >

Wei Chen^*, Dingdan Liu, Yue Liang

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.5, pp. 915-938, 2024, DOI:10.32604/fdmp.2024.046335 - 07 June 2024

Abstract This study focuses on the effect of ultrafine waste glass powder on cement strength, gas permeability and pore structure. Varying contents were considered, with particle sizes ranging from 2 to 20 μm. Moreover, alkali activation was considered to ameliorate the reactivity and cementitious properties, which were assessed by using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and specific surface area pore size distribution analysis. According to the results, without the addition of alkali activators, the performance of glass powder mortar decreases as the amount of glass powder increases, affecting various aspects such as strength… More >

Jiaxiang Wang¹, Zhengyi Li¹, Peng Shi¹, Hongying Yu², Dongbai Sun^1,3,*

CMC-Computers, Materials & Continua, Vol.79, No.1, pp. 1187-1204, 2024, DOI:10.32604/cmc.2024.046929 - 25 April 2024

Abstract Scanning electron microscopy (SEM) is a crucial tool in the field of materials science, providing valuable insights into the microstructural characteristics of materials. Unfortunately, SEM images often suffer from blurriness caused by improper hardware calibration or imaging automation errors, which present challenges in analyzing and interpreting material characteristics. Consequently, rectifying the blurring of these images assumes paramount significance to enable subsequent analysis. To address this issue, we introduce a Material Images Deblurring Network (MIDNet) built upon the foundation of the Nonlinear Activation Free Network (NAFNet). MIDNet is meticulously tailored to address the blurring in images… More >

Wei Chen^*, Wuwen Liu, Yue Liang

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.4, pp. 859-872, 2024, DOI:10.32604/fdmp.2023.029310 - 28 March 2024

Abstract River sand is an essential component used as a fine aggregate in mortar and concrete. Due to unrestrained exploitation, river sand resources are gradually being exhausted. This requires alternative solutions. This study deals with the properties of cement mortar containing different levels of manufactured sand (MS) based on quartzite, used to replace river sand. The river sand was replaced at 20%, 40%, 60% and 80% with MS (by weight or volume). The mechanical properties, transfer properties, and microstructure were examined and compared to a control group to study the impact of the replacement level. The More >

Weida Wu, Yiqiang Wang, Zhonghao Gao, Pai Liu^*

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.2, pp. 2001-2026, 2024, DOI:10.32604/cmes.2023.046670 - 29 January 2024

Abstract Negative Poisson’s ratio (NPR) metamaterials are attractive for their unique mechanical behaviors and potential applications in deformation control and energy absorption. However, when subjected to significant stretching, NPR metamaterials designed under small strain assumption may experience a rapid degradation in NPR performance. To address this issue, this study aims to design metamaterials maintaining a targeted NPR under large deformation by taking advantage of the geometry nonlinearity mechanism. A representative periodic unit cell is modeled considering geometry nonlinearity, and its topology is designed using a gradient-free method. The unit cell microstructural topologies are described with the… More >

Chenxi Xiu^1,2,*, Xihua Chu²

CMES-Computer Modeling in Engineering & Sciences, Vol.138, No.3, pp. 2305-2338, 2024, DOI:10.32604/cmes.2023.030194 - 15 December 2023

Abstract This paper presents a micromechanics-based Cosserat continuum model for microstructured granular materials. By utilizing this model, the macroscopic constitutive parameters of granular materials with different microstructures are expressed as sums of microstructural information. The microstructures under consideration can be classified into three categories: a medium-dense microstructure, a dense microstructure consisting of one-sized particles, and a dense microstructure consisting of two-sized particles. Subsequently, the Cosserat elastoplastic model, along with its finite element formulation, is derived using the extended Drucker-Prager yield criteria. To investigate failure behaviors, numerical simulations of granular materials with different microstructures are conducted using… More >

Wei Shi^1,2, Zhengyi Li¹, Xiaobing Xu¹, Yingshui Yu¹, Xiaofei Ding¹, Heng Ju^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.1, pp. 97-108, 2024, DOI:10.32604/fdmp.2023.029028 - 08 November 2023

Abstract Two-dimensional carbon/carbon (2D C/C) composites are a special class of carbon/carbon composites, generally obtained by combining resin-impregnated carbon fiber clothes, which are then cured and carbonized. This study deals with the preparation of a protective coating for these materials. This coating, based on graphite, was prepared by the slurry method. The effect of graphite and phenolic resin powders with different weight ratios was examined. The results have shown that the coating slurry can fill the pores and cracks of the composite surface, thereby densifying the surface layer of the material. With the increase of the… More >

Junpeng Lyu¹, Hai Mei^1,2, Liping Zu¹, Lisheng Liu^1,2,*, Liangliang Chu^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.138, No.1, pp. 391-410, 2024, DOI:10.32604/cmes.2023.030614 - 22 September 2023

Abstract This article proposes a modeling method for C/C-ZrC composite materials. According to the superposition of Gaussian random field, the original gray model is obtained, and the threshold segmentation method is used to generate the C-ZrC inclusion model. Finally, the fiber structure is added to construct the microstructure of the three-phase plain weave composite. The reconstructed inclusions can meet the randomness of the shape and have a uniform distribution. Using an algorithm based on asymptotic homogenization and finite element method, the equivalent thermal conductivity prediction of the microstructure finite element model was carried out, and the… More >