Yabin Yang^1,*, Yanfei Wang¹, Quan Li²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.25, No.1, pp. 1-1, 2023, DOI:10.32604/icces.2023.09842

Abstract Residual stresses and deformations are one of the challenges needs to solve for metal additive manufacturing part. Finite element method plays an important role in predicting the residual stresses and deformations to reduce the experimental costs, and provides a powerful tool for the optimization of process parameters and scanning strategies of heat source. However, the key problem in simulation is the mismatch between the melt pool and the built part in both spatial and temporal scale. This would result in large discretization in both spatial and temporal domains in the simulation, which gives rise to… More >

Aouatif Saad^1,*, Mohammed EL Ganaoui²

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.1, pp. 95-103, 2023, DOI:10.32604/fdmp.2023.022014 - 02 August 2022

Abstract Resin transfer molding (RTM) is among the most used manufacturing processes for composite parts. Initially, the resin cure is initiated by heat supply to the mold. The supplementary heat generated during the reaction can cause thermal gradients in the composite, potentially leading to undesired residual stresses which can cause shrinkage and warpage. In the present numerical study of these processes, a one-dimensional finite difference method is used to predict the temperature evolution and the degree of cure in the course of the resin polymerization; the effect of some parameters on the thermal gradient is then More >

Hiroshi Okada^*, Tatsuro Ishizaka, Akira Takahashi, Koichiro Arai, Yasunori Yusa

The International Conference on Computational & Experimental Engineering and Sciences, Vol.21, No.1, pp. 10-11, 2019, DOI:10.32604/icces.2019.05037

Abstract In this paper, a new three-dimensional J-integral for non-homogeneous solids undergoing large deformation and associated with residual stresses is presented. The formulation of J-integral involves the strain energy density W that is generally defined by the integral W = ∫₀^t τ_ijε^·_ijdt⁻ over the entire deformation history of a material point where t_ij and ε^·_ij are the components of the Kirchhoff stress and those of velocity strain. t and t represents the time. It is assumed that at t = 0 the body is free from any deformation and therefore the stresses are zeros.
Residual stresses are induced by… More >

Davood Afshari^1,*, Soheil Mirzaahamdi¹, Zuheir Barsoum²

CMES-Computer Modeling in Engineering & Sciences, Vol.118, No.2, pp. 275-290, 2019, DOI:10.31614/cmes.2019.03880

Abstract The use of magnesium alloys has been rapidly increased due to their ability to maintain high strengths at light weights. However weldability of steels and aluminum alloys by using resistance spot weld (RSW) process is a major issue, because it cannot be directly utilized for magnesium alloys. In this study, a structural-thermal-electrical finite element (FE) model has been developed to predict the distribution of residual stresses in RSW AZ61 magnesium alloy. Thermophysical and thermomechanical properties of AZ61 magnesium alloy have been experimentally determined, and have been used in FE model to increase the accuracy of… More >

Shanshan Huo, Chad A. Ulven^*

Journal of Renewable Materials, Vol.5, Suppl.1, pp. 106-116, 2017, DOI:10.7569/JRM.2017.634136

Abstract The development of flax fiber reinforced polymer composites with improved properties has been increasingly studied by many researchers because of their sustainability. However, the effects of thermal residual stresses on the interfacial properties of flax composites have not been evaluated or very well understood. In this study, the thermal properties of flax, vinyl ester matrices and their composites were accessed by different techniques, including thermomechanical analyzer, dynamic mechanical analyzer, and X-ray diffraction combined with aluminum particles. The effects of thermal properties of flax fibers and vinyl ester resin systems on the mechanical properties of their More >

J. Solórzano-López¹, F.A. García-Pastor², Angélica Flores-Luna³

CMC-Computers, Materials & Continua, Vol.51, No.3, pp. 203-215, 2016, DOI:10.3970/cmc.2016.051.203

Abstract Shot peening is a widely used technique to improve fatigue life in metallic alloys. This processing technique introduces a subsurface compressive residual stress field through a plastic deformation of the surface caused by the impact of a large number of high-speed projectiles. There are a number of parameters that affect the residual stress field depth and magnitude. The effects of the impact angle, shot speed and shot geometry are currently being researched. In particular, substituting spherical cast shots by cylindrical cut wire shots is an attractive option, especially in terms of cost. The effect of… More >

Xing Wei^1,2, Wen Chen^1,3, Bin Chen¹

CMC-Computers, Materials & Continua, Vol.48, No.1, pp. 1-23, 2015, DOI:10.3970/cmc.2015.048.001

Abstract The thermal residual stress in the fabrication of functionally graded material (FGM) systems can give rise to various mechanical failures. For a FGM system under a given fabrication environment, the thermal residual stresses are determined by the spatial distribution of its constituent components. In this study, we optimize a Ni/Al₂O₃ FGM plate aiming at minimizing the thermal residual stresses through controlling its compositional distribution. Material properties are graded in the thickness direction following a power law distribution in terms of the volume fractions of constituents (P-FGM). An analytical model and a hybrid genetic algorithm with the More >

G. Nicoletto¹, A. Saletti²

Structural Durability & Health Monitoring, Vol.8, No.2, pp. 131-148, 2012, DOI:10.3970/sdhm.2012.008.131

Abstract Fatigue strengthening of fillets by deep rolling is finding increased application for example in engine crankshaft production for functional and economical reasons. A fatigue design method aimed at exploiting the residual stresses that develop at a notched part following the rolling process is proposed. It is based on the superposition of residual stresses obtained by elastic-plastic FE simulation of the rolling process and the cyclic elastic stresses within a Haigh diagram framework. The fatigue design method is assessed using the experimental evidence obtained by testing notched specimens made of 30NiCrMo12 steel subjected to different rolling More >

S.M. Häusler¹, P.M. Baiz², S.M.O. Tavares³, A. Brot⁴, P. Horst¹, M.H. Aliabadi², P.M.S.T. de Castro³, Y. Peleg-Wolfin⁴

Structural Durability & Health Monitoring, Vol.7, No.3, pp. 163-190, 2011, DOI:10.3970/sdhm.2011.007.163

Abstract This article represents the first part of a two-part article which presents, compares and discusses the different crack growth simulation models which were introduced for fatigue crack growth assessment during the DaToN project. The project was funded by the EC within the 6th framework program and was specifically devoted to investigate innovative manufacturing techniques for metallic structures with special focus on the effects of residual stresses on the fatigue crack growth and residual strength behaviour. Within this first part the different simulation approaches, including the residual stress modelling approaches will be introduced and stress intensity… More >

M. Guagliano^1,2, S. Bagherifard², I. Fernandez Parienete³, R. Ghelichi²

Structural Durability & Health Monitoring, Vol.6, No.1, pp. 31-42, 2010, DOI:10.3970/sdhm.2010.006.031

Abstract Surface grain refinement is a relatively new process aimed to enhance mechanical material properties. In this study Al7075-T6 bars have been shot peened with parameters (shot speed and treatment duration) much stronger from those of conventional shot peening (SP). Residual stress state and microstructure gradient have been observed by means of transmission electron microscopy (TEM), X-ray diffraction (XRD) and nano indentation tester. Formation of a fine grained layer of material on top surface of the specimens was confirmed by TEM and also XRD measurements. XRD results show significant depth affected both in terms of residual More >