Welding Metallurgy of

3D-imaging of selective laser melting defects in a Co–Cr–Mo alloy by synchrotron radiation micro-CT

Numerical analysis of heat transfer and fluid flow in multilayer deposition of PAW-based wire and arc additive manufacturing

Transportation industries are obliged to address concerns arising from greater emphasis on energy saving and ecologically sustainable products. Engineers, therefore, have a responsibility to deliver innovative solutions that will support environmental preservation and yet meet industries’ requirements for greater productivity and minimised operational costs. Aluminium alloys have successfully contributed to meeting the rising demand for lightweight structures. Notable developments in aluminium welding techniques have resolved many welding related problems, although some issues remain to be addressed. The present study attempts to give an overview of the key factors related to the formation of defects in welding methods commonly used with aluminium alloys. First, a concise overview of defects found in friction-stir welding, laser beam welding and arc welding of aluminium alloys is presented. The review is used as a basis for analysis of the relationship between friction-stir welding process parameters and weld defects. Next, the formation and prevention of the main weld defects in laser beam welding, such as porosity and hot cracking, are discussed. Finally, metallurgical aspects influencing weld metal microstructure and contributing to defects are tabulated, as are defect prevention methods, for the most common flaws in arc welding of aluminium alloys.

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Investigation of weld defects in friction-stir welding and fusion welding of aluminium alloys

Numerical and experimental study of arc and weld pool behaviour for pulsed current GTA welding

Weld pool dynamics and the formation of ripples in 3D gas metal arc welding

https://web.mst.edu/~tsai/published papers/guo-ijhmt-2009.pdf

Formation of weld crater in GMAW of aluminum alloys

This article studies the transient weld pool dynamics under the periodical impingement of filler droplets that carry mass, momentum, thermal energy, and species in a moving 3D gas metal arc welding. The complicated transport phenomena in the weld pool are caused by the combined effect of droplet impingement, gravity, electromagnetic force, plasma arc force, and surface tension force (Marangoni effect). The weld pool shape and the distributions of temperature, velocity, and species in the weld pool are calculated as a function of time. The phenomena of “open and close-up” for a crater in the weld pool and the corresponding weld pool dynamics are analyzed. The commonly observed ripples at the surface of a solidified weld bead are, for the first time, predicted by the present model. Detailed mechanisms leading to the formation of ripples are discussed.Copyright © 2007 by ASME

/pdf/weld-pool-dynamics-and-the-formation-of-ripples-in-3d-gas-2fe7th415z.pdf

H. Guo

Papers

Weld pool dynamics and the formation of ripples in 3D gas metal arc welding

Formation of weld crater in GMAW of aluminum alloys

Weld Pool Dynamics and the Formation of Ripples in 3D Gas Metal Arc Welding