Measurement and analysis of welding deformation and residual stress in CMT welded lap joints of 1180 MPa steel sheets

AbstractTargeted magnetic flux guidance in the rotor cross section of rotational electrical machines is crucial for the machine’s efficiency. Cutouts in the electrical steel sheets are integrated in the rotor sheets for magnetic flux guidance. These cutouts create thin structures in the rotor sheets which limit the maximum achievable rotational speed under centrifugal forces and the maximum energy density of the rotating electrical machine. In this paper, embossing-induced residual stress, employing the magneto-mechanical Villari effect, is studied as an innovative and alternative flux barrier design with negligible mechanical material deterioration. The overall objective is to replace cutouts by embossings, increasing the mechanical strength of the rotor. The identification of suitable embossing geometries, distributions and methodologies for the local introduction of residual stress is a major challenge. This paper examines finely distributed pyramidal embossings and their effect on the magnetic material behavior. The study is based on simulation and measurements of specimen with a single line of twenty embossing points performed with different punch forces. The magnetic material behavior is analyzed using neutron grating interferometry and a single sheet tester. Numerical examinations using finite element analysis and microhardness measurements provide a more detailed understanding of the interaction of residual stress distribution and magnetic material properties. The results reveal that residual stress induced by embossing affects magnetic material properties. Process parameters can be applied to adjust the magnetic material deterioration and the effect of magnetic flux guidance.

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Numerical analysis of welding deformation and residual stress in marine propeller nozzle with hybrid laser-arc girth welds

International Journal of Pressure Vessels and Piping ◽

10.1016/j.ijpvp.2017.10.007 ◽

2017 ◽

Vol 158 ◽

pp. 51-58 ◽

Cited By ~ 5

Author(s):

Youmin Rong ◽

Yong Chang ◽

Jiajun Xu ◽

Yu Huang ◽

Ting Lei ◽

...

Keyword(s):

Residual Stress ◽

Numerical Analysis ◽

Welding Deformation ◽

Marine Propeller ◽

Girth Welds

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Prediction of Residual Stress and Welding Deformation Generated by Pipe Welding Through the Medium of Inherent Strain.

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series A ◽

10.1299/kikaia.66.374 ◽

2000 ◽

Vol 66 (642) ◽

pp. 374-381 ◽

Cited By ~ 7

Author(s):

Toshiharu NOMOTO ◽

Toshio TERASAKI

Keyword(s):

Residual Stress ◽

Welding Deformation ◽

Pipe Welding ◽

Inherent Strain

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Study on Welding Deformation and Residual Stress of H-Section Beam Based on Finite Element Method

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.753.305 ◽

2017 ◽

Vol 753 ◽

pp. 305-309 ◽

Cited By ~ 1

Author(s):

Xu Lu

Keyword(s):

Mechanical Properties ◽

Residual Stress ◽

Finite Element ◽

Source Parameters ◽

Welding Process ◽

Steel Structure ◽

Bottom Plate ◽

Welding Deformation ◽

Element Simulation ◽

Main Components

The welding H-section beam has good mechanical properties with its superior structure. So they become the main components of steel structure and have been widely used. In this paper, the welded H-section beam is used as the research object. The finite element simulation model is established. The heat source parameters are determined. The deformation of the steel due to the welding process is studied. The results show that the bottom plate and the bottom plate inward bending is about 2.32mm cause by welding process. The residual stress can reach 400MPa.

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Spot Weldability Assessment of Similar and Dissimilar Steel Sheets for Light Weight Automobile Body

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.306-308.899 ◽

2006 ◽

Vol 306-308 ◽

pp. 899-904

Author(s):

Dong Ho Bae ◽

Won Seok Jung ◽

J.B. Heo

Keyword(s):

Stainless Steel ◽

Fatigue Strength ◽

Lap Joints ◽

Vehicle Body ◽

Rolled Steel ◽

Cold Rolled Steel ◽

Steel Sheets ◽

Automobile Body ◽

Cold Rolled ◽

Spot Welded

An effective way to reduce the weight of vehicle body seems to be application of new materials, and such trend is remarkable. Among the various materials for automobile body, stainless steel sheets and cold rolled steel sheets are under the interests. However, in order to guarantee reliability of new material and to establish the long life fatigue design criteria for body structure, it is necessary to assess spot weldability and fatigue strength of spot welded lap joints fabricated under optimized spot welding condition. In this paper, spot weldability of stainless steel sheets, STS301L and STS304L, and cold rolled steel sheets, SPCC and SPCD. Fatigue strength of lap joints spot welded between similar and dissimilar materials were also assessed.

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