A. MADHAN KUMAR¹, K. JAYAKUMAR^2,*, M. SHALINI³

Journal of Polymer Materials, Vol.39, No.3-4, pp. 269-281, 2022, DOI:10.32381/JPM.2022.39.3-4.7

Abstract Polylactic acid (PLA) is the most popular thermoplastic biopolymer providing a stiffness and strength alternative to fossil-based plastics. It is also the most promising biodegradable polymer on the market right now, thus gaining a substitute for conservative artificial polymers. Therefore, the current research focuses on synthesizing and mechanical characterization of particlereinforced PLA composites. The hot compression molding technique was used to fabricate PLA-based composites with 0, 2.5, 5, and 7.5 weight % of sawdust, rice husk, and bagasse particle reinforcements to enhance the performance of the PLA. The pellets of PLA matrix were taken with an average size of 3… More >

DIBYENDU S. BAG^*, SHILPI TIWARI, AKANSHA DIXIT, KM. MEENU

Journal of Polymer Materials, Vol.40, No.1-2, pp. 105-123, 2023, DOI:10.32381/JPM.2023.40.1-2.9

Abstract In this paper, we report the microstructural investigation and influence of H-bonding on the thermal behavior e.g., glass transition (T_g ) and thermal degradation of chiral copolymers of (R)- N-(1-phenyl-ethyl) methacrylamide (R-NPEMAM) and 2-hydroxy ethyl methacrylate (HEMA). The T_g increases with the increase of chiral unit content in the copolymers and then attains optimum at around 25 mole % of chiral content. Thereafter it decreases with the increase of chiral content. The effect of copolymer composition and secondary interaction associated with the Hbonding on the thermal properties of these copolymers was also studied. Secondary interaction, specifically H-bonding has been interpreted… 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

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 results indicate that the compressive… 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

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 material-field series-expansion (MFSE) method. The… More >

Wenzhen Xia^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.3, pp. 1-1, 2023, DOI:10.32604/icces.2023.09758

Abstract Microstructural alteration of tribo-elements' the near-surface region significantly affects how long a tribosystem will last. To design and tailor future surfaces of tribo-elements, a fundamental understanding of microstructure evolution under local tribological exposure is required. During the initial steps of macrotribological process in metals, horizontal dislocation walls have been observed, which later develop into the grain-refined tribolayer, however, their fundamental mechanisms are yet unknown. In this work, we developed a novel micro-tribological test, in order to directly inspect the contact zone and simplify the stress status. Our preliminary basic tribological experiments identify grain orientation and twin boundary effects in dry… More >

Wenjun Chen¹, Yingjun Wang^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.3, pp. 1-1, 2023, DOI:10.32604/icces.2023. 09096

Abstract The rapid development of topology optimization has given birth to a large amount of different topology optimization methods, and each of them can manage a class of corresponding engineering problems. However, structures need to meet a variety of requirements in engineering application, such as lightweight and multiple load-bearing performance. To design composite structures that have multiple structural properties, a new multi-scale topology optimization method considering multiple structural performances is proposed in this paper. Based on the fitting functions of the result set and the bisection method, a new method to determine the weight coefficient is proposed in this paper, which… 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

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 the ABAQUS User Element (UEL)… More >

Hui Jiang^a,b, Daming Wu^a,b,c, Jian Zhuang^a,b,*, Ying Liu^a,b,c, Changqing Huang^a,b

Frontiers in Heat and Mass Transfer, Vol.6, pp. 1-6, 2015, DOI:10.5098/hmt.6.14

Abstract A new type of metal-plastic composite heat radiator with hemispherical microstructure array was proposed in this paper. The influence of the geometrical parameters of the microstructure array, including size of the hemisphere, configuration of hemisphere, tilt angle of the radiator, thermal conductivity and radiation emissivity of the plastic, on the process of heat transfer under natural convection were numerically simulated. It was concluded that the metal-plastic composite heat radiator with hemispherical microstructure array had comparable heat transfer behaviors with those of metal heat radiator. So it is possible to replace metal heat radiator by such a metal-plastic composite heat radiator… 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

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 graphite powder/phenolic resin weight ratio,… More >

Cheng Hu^1,2, Weiheng Xiang^1,3,*, Ping Chen^2,3, Yi Yang^4,5, Libo Zhou³, Jiufang Jiang⁵, Shunkai Li^2,4, Yang Ming¹, Qing Li³

Journal of Renewable Materials, Vol.11, No.11, pp. 3945-3956, 2023, DOI:10.32604/jrm.2023.027544

Abstract The aim of this study is to enhance the value and utilization of red mud generated in the Bayer process by preparing composite cement mortars. The effects of two different types of Bayer red mud with varying physical and chemical characteristics on the fluidity, mechanical strength, mineral composition, and microstructure of the composite cement mortar were systematically evaluated. The results showed that the optimal addition of red mud A was 10 wt%, while it was 20 wt% for red mud B. The mechanical properties of the composite cement mortar met the standards for P·O42.5 cement. Furthermore, the composite mortar with… More >