Author： Campbell S W Galloway A M McPherson N A
Publisher： Maney Publishing
ISSN： 1743-2936
Source： Science and Technology of Welding & Joining, Vol.18, Iss.7, 2013-10, pp. : 597-602
Disclaimer: Any content in publications that violate the sovereignty, the constitution or regulations of the PRC is not accepted or approved by CNPIEC.
Abstract
The transient variation of the shielding gas present in the alternating shielding gas process produces a dynamic action within the liquid weld metal. Flow vectors opposite in direction have been reported due to the various forces acting on the weld metal when argon and helium are present; however, no data have been provided to substantiate this claim. This part of the study evaluates the various forces acting on the liquid weld metal when using argon and helium, and their effects are discussed. It was determined that argon produces a greater vertically downward force in the central region than does helium for both the arc force and Lorentz force. However, helium produces a greater radially outward force at the pool surface than does argon due to plasma shear stress and Marangoni convection. In addition, the buoyancy force, i.e. the vertically upward force in the central portion of the weld metal, was greater for helium.
Related content
Access to resources
Recommend
Environmental Criteria for Shielding Gas Selection during Arc Welding of Stainless Steels
Solid State Phenomena, Vol. 2016, Iss. 246, 2016-03 ,pp. :
By Williamson Rodney Zanner Frank Grose S.
Metallurgical and Materials Transactions B, Vol. 28, Iss. 5, 1997-10 ,pp. :