Yanhua Zhao^1,3,*, Wenhao Tian¹, Jianhua Liu¹, Dongqing Qian², Wei Meng¹, Jiaming Wang¹

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.2, pp. 451-470, 2023, DOI:10.32604/fdmp.2022.021035

Abstract The process parameters of laser additive manufacturing have an important influence on the forming quality of the produced items or parts. In the present work, a finite element model for simulating transient heat transfer in such processes has been implemented using the ANSYS software, and the temperature and stress distributions related to 316L stainless steel thin-walled ring parts have been simulated and analyzed. The effect of the laser power, scanning speed, and scanning mode on temperature distribution, molten pool structure, deformation, and stress field has been studied. The simulation results show that the peak temperature, weld pool size, deformation, and… More >

Yueqiang Yu¹, Tingang Ma¹, Suling Wang^1,*, Minzheng Jiang¹, Yanling Guo^2,3, Ting Jiang^1,*, Shuaiqi Huang¹, Ziming Zheng¹, Bo Yan¹, Jiyuan Lv¹

Journal of Renewable Materials, Vol.11, No.1, pp. 333-347, 2023, DOI:10.32604/jrm.2022.022296

Abstract A calculation model of stress field in laser additive manufacturing of walnut shell composite powder (walnut shell/Co-PES powder) was established. The DFLUX subroutine was used to implement the moveable application of a double ellipsoid heat source by considering the mechanical properties varying with temperature. The stress field was simulated by the sequential coupling method, and the experimental results were in good accordance with the simulation results. In addition, the distribution and variation of stress and strain field were obtained in the process of laser additive manufacturing of walnut shell composite powder. The displacement of laser additive manufacturing walnut shell composite… More > Graphic Abstract

Jun Zou^*, Haolei Mou

CMES-Computer Modeling in Engineering & Sciences, Vol.132, No.2, pp. 451-469, 2022, DOI:10.32604/cmes.2022.020111

Abstract The integration of topology optimization (TO) and additive manufacturing (AM) technologies can create significant synergy benefits, while the lack of AM-friendly TO algorithms is a serious bottleneck for the application of TO in AM. In this paper, a TO method is proposed to design self-supporting structures with an explicit continuous self-supporting constraint, which can be adaptively activated and tightened during the optimization procedure. The TO procedure is suitable for various critical overhang angles (COA), which is integrated with build direction assignment to reduce performance loss. Besides, a triangular directional self-supporting constraint sensitivity filter is devised to promote the downward evolution… More >

Ivan Izonin^1,*, Roman Tkachenko¹, Michal Gregus², Zoia Duriagina^1,3, Nataliya Shakhovska¹

CMC-Computers, Materials & Continua, Vol.71, No.3, pp. 5933-5947, 2022, DOI:10.32604/cmc.2022.022582

Abstract The advent of additive technologies has provided a significant breakthrough in the production of medical implants. It has reduced costs, increased productivity and accuracy of the implant manufacturing process. However, there are problems associated with assessing defects in the microstructure, mechanical and technological properties of alloys, both during their production by powder metallurgy and in the process of 3D printing. Thus traditional research methods of alloys properties demand considerable human, material, and time resources. At the same time, artificial intelligence tools create opportunities for intelligent evaluation of the conformity for the microstructure, phase composition, and properties of titanium powder’s alloys.… More >

Ye Lu¹, Hengyang Li¹, Sourav Saha², Satyajit Mojumder², Abdullah Al Amin¹, Derick Suarez¹, Yingjian Liu³, Dong Qian³, Wing Kam Liu^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.129, No.3, pp. 1351-1371, 2021, DOI:10.32604/cmes.2021.017719

Abstract This paper presents the concept of reduced order machine learning finite element (FE) method. In particular, we propose an example of such method, the proper generalized decomposition (PGD) reduced hierarchical deeplearning neural networks (HiDeNN), called HiDeNN-PGD. We described first the HiDeNN interface seamlessly with the current commercial and open source FE codes. The proposed reduced order method can reduce significantly the degrees of freedom for machine learning and physics based modeling and is able to deal with high dimensional problems. This method is found more accurate than conventional finite element methods with a small portion of degrees of freedom. Different… More >

Di Wang¹, Yongqiang Yang^1,*, Yingjun Wang^1,*, Li Yang², Hao Wang³, Shoufeng Yang⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.126, No.1, pp. 1-4, 2021, DOI:10.32604/cmes.2021.015180

Abstract This article has no abstract. More >

Kang-Hyun Lee¹, Gun Jin Yun^1,2,*

CMC-Computers, Materials & Continua, Vol.66, No.1, pp. 87-112, 2021, DOI:10.32604/cmc.2020.012688

Abstract Re-melting process has been utilized to mitigate the residual stress level in the selective laser melting (SLM) process in recent years. However, the complex consolidation mechanism of powder and the different material behavior after the first laser melting hinder the direct implementation of the re-melting process. In this work, the effects of re-melting on the temperature and residual stress evolution in the SLM process are investigated using a thermo-mechanically coupled finite element model. The degree of consolidation is incorporated in the energy balance equation based on the thermodynamically-consistent phase-field approach. The drastic change of material properties due to the variation… More >

Ting Zang¹, Dongbin Zhu^2,*, Guowang Mu¹

CMES-Computer Modeling in Engineering & Sciences, Vol.125, No.2, pp. 597-610, 2020, DOI:10.32604/cmes.2020.09965

Abstract According to the requirement of heterogeneous object modeling in additive manufacturing (AM), the Non-Uniform Rational B-Spline (NURBS) method has been applied to the digital representation of heterogeneous object in this paper. By putting forward the NURBS material data structure and establishing heterogeneous NURBS object model, the accurate mathematical unified representation of analytical and free heterogeneous objects have been realized. With the inverse modeling of heterogeneous NURBS objects, the geometry and material distribution can be better designed to meet the actual needs. Radical Basis Function (RBF) method based on global surface reconstruction and the tensor product surface interpolation method are combined… More >

Donghua Dai^1,2, Dongdong Gu^1,2,*, Qing Ge^1,2, Chenglong Ma^1,2, Xinyu Shi^1,2, Han Zhang^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.3, pp. 1085-1098, 2020, DOI:10.32604/cmes.2020.010927

Abstract The three-dimensional physical model of the randomly packed powder material irradiated by the laser beam was established, taking into account the transformation of the material phase, the melt spreading and the interaction of the free surface of the molten pool and the recoiling pressure caused by the material evaporation during the selective laser melting. Influence of the processing parameters on the thermal behavior, the material evaporation, the surface morphology and the densification behavior in the connection region of the molten pool and the substrate was studied. It was shown that the powder material underwent the transformation from the partial melting… More >

Zhaohui Xia^1,2, Zhihao He², Qifu Wang¹, Yingjun Wang^2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.2, pp. 703-720, 2020, DOI:10.32604/cmes.2020.010368

Abstract Additive manufacturing (AM), adding materials layer by layer, can be used to produce objects of almost any shape or geometry. However, AM techniques cannot accurately build parts with large overhangs, especially for the large features close to horizontal, hanging over the void. The overhangs will make the manufactured model deviate from the design model, which will result in the performance of the manufactured model that cannot satisfy the design requirements. In this paper, we will propose a new finite element (FE) analysis model that includes the manufacturing errors by mimicking the AM layer by layer construction process. In such FE… More >