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 huge computational cost. Therefore, it… 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

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 analyzed, namely: the fiber nature,… 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 biocomposites were studied. The theory… 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 process parameters. 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 factor results will be presented… 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 stress and full width half… More >

R. Ghelichi¹, S. Bagherifard¹, I. Fernandez Parienete², M.Guagliano^1,3, Simone Vezzù⁴

Structural Durability & Health Monitoring, Vol.6, No.1, pp. 17-30, 2010, DOI:10.3970/sdhm.2010.006.017

Abstract Coating deposition processes such as cold spraying are commonly employed to increase wear and fatigue resistance and consequently to enhance longevity of engineering components. Such processes typically introduce residual stresses into the coated surface, which in turn affect efficiency of coatings and play an important role in coating durability. In fact residual stresses are the key parameter to obtain compact and well-adherent coatings. They can modify several coating properties such as adhesion, structure, toughness, hardness reflecting on the macroscopic chemical and mechanical behavior of the coating.
Present study describes alteration of residual stress state of two types of aluminum coatings… More >

S. Baragetti¹, F. Tordini²

Structural Durability & Health Monitoring, Vol.3, No.3, pp. 165-176, 2007, DOI:10.3970/sdhm.2007.003.165

Abstract The effect of a TiN PVD (Physical Vapor Deposition) coating on the fatigue behaviour of the titanium alloy Ti-6Al-4V was investigated. Fatigue tests were performed on coated and uncoated, both smooth and 120° V-notched, specimens in order to evaluate the influence of the coating on the substrate fatigue resistance. Numerical analyses were carried out in order to determine the stress distributions below the specimen surface and on the coating. Several coating elastic moduli were used in such calculations. The residual stress gradient induced by the coating process deposition and the substrate plasticization were also taken into account with FEM. The… More >

S. Baragetti¹, A. Terranova²

Structural Durability & Health Monitoring, Vol.1, No.4, pp. 267-276, 2005, DOI:10.3970/sdhm.2005.001.267

Abstract Aim of this work is to investigate into the possibility of enhancing the fatigue resistance of CrN PVD coated components. In particular PVD coated spur gears were tested and numerical simulation of crack propagation was carried out. The coating layer micro-hardness and the residual stresses characterising the surface film were measured and the obtained results were introduced in a numerical modelling predicting fatigue life procedure of coated gears used in gearboxes for automotive applications. The number of cycles necessary to reach specified crack depths of coated and uncoated samples was numerically determined and represents a powerful tool to predict fatigue… More >

K.Y. Volokh¹

Molecular & Cellular Biomechanics, Vol.2, No.2, pp. 77-86, 2005, DOI:10.3970/mcb.2005.002.077

Abstract Recently Volokh and Lev (2005) argued that residual stresses could appear in growing arteries because of the arterial anisotropy. This conclusion emerged from a continuum mechanics theory of growth of soft biological tissues proposed by the authors. This theory included Lagrangian constitutive equations, which were formulated directly with respect to the reference configuration. Alternatively, it is possible to formulate Eulerian constitutive equations with respect to the current configuration and to 'pull them back' to the reference configuration. Such possibility is examined in the present work. The Eulerian formulation of the constitutive equations is used for a study of arterial growth.… More >