INVESTIGATION OF THE INFLUENCE OF A-PILLAR ON PASSIVE SAFETY OF A VEHICLE IN CASE OF ROLLOVER

The need for the means ensuring passive safety of a vehicle is becoming increasingly emphasized in the area of transport engineering. This area becomes particularly relevant when restoration of the damaged load bearing structures in vehicles is concerned. When performing restoration and modification of the vehicles according to specific needs or repairing them after traffic accidents, the lack of norms giving formalized determination of passive safety and recommendations for its assurance becomes obvious. Computational model of the roof structure developed in LSDYNA is presented, the weld intended for the structure joints is modelled, and residual stresses due to welding process are taken into account, the most effective model of weld location for A-pillar is selected and the influence of A-pillar on the strength of vehicle’s roof structure is determined in case of quasi-static compression.

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Characterization and Evaluation of Mechanical Properties and Residual Stress in Aluminum-Magnesium Alloys Welded by the FSW Process

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1012.349 ◽

2020 ◽

Vol 1012 ◽

pp. 349-353

Author(s):

D.B. Colaço ◽

M.A. Ribeiro ◽

T.M. Maciel ◽

R.H.F. de Melo

Keyword(s):

Mechanical Properties ◽

Residual Stress ◽

Residual Stresses ◽

Welding Process ◽

Bending Test ◽

Uniaxial Tensile ◽

Uniaxial Tensile Test ◽

Friction Stir ◽

Aluminum Magnesium Alloys

The demand for lighter materials with suitable mechanical properties and a high resistance to corrosion has been increasing in the industries. Therefore, aluminum appears as an alternative due to its set of properties. The aim of this work was to evaluate residual stress levels and mechanical properties of welded joints of Aluminum-Magnesium alloy AA 5083-O using the Friction Stir Welding process. For mechanical characterization were performed a uniaxial tensile test, Vickers hardness, bending test and, finally, the determination of residual stresses. It was concluded that welding by FSW process with an angle of inclination of the tool at 3o, established better results due to better mixing of materials. The best results of tensile strength and a lower level of residual stresses were obtained using a tool rotation speed of 340 RPM with welding advance speed of 180 mm/min and 70 mm/min.

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A Computational Model of Backlay Welding for Controlling Residual Stresses in Welded Pipes

Journal of Pressure Vessel Technology ◽

10.1115/1.3263395 ◽

1981 ◽

Vol 103 (3) ◽

pp. 226-232 ◽

Cited By ~ 22

Author(s):

F. W. Brust ◽

E. F. Rybicki

Keyword(s):

Residual Stress ◽

Residual Stresses ◽

Computational Model ◽

Welding Process ◽

Computational Results ◽

Intergranular Stress Corrosion ◽

Inner Surface ◽

Piping Systems ◽

Intergranular Stress Corrosion Cracking ◽

Compressive Residual Stresses

Intergranular Stress Corrosion Cracking (IGSCC) has been a problem in Boiling Water Reactor (BWR) piping systems. One method for retarding IGSCC is to eliminate tensile residual stresses at the pipe inner surface in the heat affected zone produced by the welding process. A method called backlay welding can be effective in producing compressive residual stresses at the pipe inner surface. This paper describes a computational model and its use in examining the effectiveness of the backlay welding process. The model has demonstrated an ability to predict weld-induced residual stresses for a variety of pipe sizes and welding conditions. Computational results for backlay welding are in agreement with residual stress data. The mechanisms causing residual stresses and the effect of the number of backlay weld layers on residual stresses are discussed.

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Determination of 2A16 Constitutive Model

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.631-632.412 ◽

2013 ◽

Vol 631-632 ◽

pp. 412-416 ◽

Cited By ~ 1

Author(s):

Jiang Hua Deng ◽

Chao Tang ◽

Yan Ran Zhan ◽

Xing Ying Jiang

Keyword(s):

Constitutive Model ◽

Strain Rate ◽

Strain Rate Range ◽

Static Compression ◽

Shpb Test ◽

Strain Rate Hardening ◽

Electromagnetic Riveting ◽

Quasi Static Compression ◽

Good Agreement

The stress-strain curves of 2A16 under different strain rate range (10-3s-1-103s-1) and different temperature range (293K-673K) were obtained through the quasi-static compression test and SHPB test by experimental method. The parameters were determined based on Johnson-Cook model and the strain rate hardening term in them was modified. The results show that 2A16 is a kind of strain rate and sensitive temperature materials. The flow stress increases with strain rate increasing, while that decreases with temperature increasing. The deviation is large between the unamended Johnson-Cook constitutive model and test data, while the modified constitutive model is a good agreement with experimental results. And the study is a preparation for the numerical simulation of 2A16 rivet electromagnetic riveting.

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Residual Stresses Evaluation on Radial Friction Welded Joints

24th International Conference on Offshore Mechanics and Arctic Engineering: Volume 3 ◽

10.1115/omae2005-67080 ◽

2005 ◽

Cited By ~ 1

Author(s):

Rosa Irene Terra Pinto ◽

Telmo Roberto Strohaecker

Keyword(s):

Residual Stresses ◽

Friction Welding ◽

Deformation Gradient ◽

Welding Process ◽

Hole Drilling ◽

Welding Parameters ◽

Hole Drilling Method ◽

Joint Quality ◽

Welding Processes

The Radial Friction Welding (RFW) is a solid-state welding process in which two long elements of several metallic alloys can be joined, without the occurrence of common problems to the conventional welding processes that include fusion. During friction welding the temperature evolution is directly related with the deformation gradient, and these fields govern the joint properties. In this work, the finite element method was used to solve the full coupled termomechanical problem in order to determine the deformation and the stress fields and the variation of the temperature during RFW process. The simulation of the RFW process permitted to establish the influence of the welding parameters, like rotation and approximation speed, on the joint quality. Furthermore, the knowledge of the temperature gradient and cooling rates allowed the prediction of the resulting microestruture and determination of the level of residual stresses of the joint. To verify the analytical results the determination of the residual stresses was accomplished by the hole drilling method in several points along the perimeter of two welded workpieces.

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Measurement of Residual Stresses Near the Surface Using the Crack Compliance Method

Journal of Engineering Materials and Technology ◽

10.1115/1.2903392 ◽

1991 ◽

Vol 113 (2) ◽

pp. 199-204 ◽

Cited By ~ 23

Author(s):

W. Cheng ◽

I. Finnie ◽

O¨. Vardar

Keyword(s):

Residual Stress ◽

Residual Stresses ◽

Computational Model ◽

Strain Measurement ◽

Stress Measurement ◽

Residual Stress Measurement ◽

Hole Drilling ◽

Hole Drilling Method ◽

Drilling Method

The use of thin cuts for residual stress measurement is referred to as the crack compliance method. A computational model is presented for the determination of normal and shear residual stresses near the surface by introducing shallow cuts. The optimum regions for strain measurement are obtained. This method is shown to be considerably more sensitive than the conventional hole drilling method and is capable of measuring residual stresses which vary with depth below the surface.

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Residual Stress Effects in Stiffened Structures - An Alternative Approach

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.417-418.757 ◽

2009 ◽

Vol 417-418 ◽

pp. 757-760 ◽

Cited By ~ 2

Author(s):

Peter Horst ◽

Sascha Marc Häusler

Keyword(s):

Residual Stresses ◽

Welding Process ◽

Growth Behavior ◽

Crack Growth Behavior ◽

Intensity Factors ◽

Stress Effects ◽

Alternative Approach ◽

Stiffened Structures ◽

The One

The fatigue crack growth behavior in integrally stiffened, welded panels is influenced by residual stresses caused by the welding process. The paper presents a semi-numerical method for the determination of stress intensity factors, taking into account the residual stresses in such a way that the relaxation of the residual stresses during the crack propagation phase is covered. This approach is different from the one presented in [1].

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