Shielding gas

About: Shielding gas is a research topic. Over the lifetime, 6697 publications have been published within this topic receiving 58668 citations.

Method of and device for arc welding

Abstract: A method of plasma MIG welding in which an arc is maintained between a workpiece and a welding wire in a thermally ionized gas (auxiliary plasma) which is generated by an electric gas-discharge between two non-consumable electrodes; neither the welding wire nor the workpiece acts as a single electrode for generating the thermally ionized gas.

Gas metal arc welding of aluminum-based workpieces

Abstract: Method of welding aligned aluminum torque tube components, comprising (i) defining a stepped square-butt joint to be welded by preforming the ends of said torque tubes and assembling such ends together in the nested condition; (ii) establishing an electrical direct current arc between a positive consumable aluminum-based electrode and said joint as cathode, the arc being shrouded in a shielding gas consisting, by volume, of 2-5% oxygen and the remainder inert gas, the current to the arc being pulsed at a frequency of 40-60 cycles per second while maintaining an average current of at least 200 amps; and (iii) while holding the pulsed arc in a predetermined orientation (i.e., position angle 45-60°, lead angle 5-15°, transverse angle 12°) to the joint, moving the arc along the joint in a single pass at a relative speed of at least 60 inches per minute.

Modulated spray mig welding process and device

Abstract: A process and a device for the gas-shielded MIG welding in modulated-spray mode, of aluminum, particularly aluminum alloys, or stainless steels, in which the current is modulated at a modulation frequency of less than 60 Hz. The shielding gas contains at least 90% helium, argon or a mixture thereof and at most 1.95% of at least one minor gaseous component chosen from oxygen and carbon dioxide. This process allows effective degassing of most of the diffusible hydrogen liable to be found in the pool of molten metal and improves the appearance and quality of the weld beads thus produced on workpieces or equipment intended for the rail, sea, air, road or space transport industry or for the chemical, petrochemical, electronic, nuclear or agrochemical industries.

Improvement of mechanical properties of gas tungsten arc and electron beam welded AA2219 (Al–6 wt-%Cu) alloy

Abstract: Despite its excellent weldability characteristics, AA2219 suffers from poor fusion zone strength under the as welded condition. In the present work, it is attempted to increase the mechanical properties of the as welded fusion zone of this alloy by increasing the weld cooling rates and multipass welding. The cooling rate was increased with the use of high intense heat source, namely electron beam in a pulsed current mode. Multipass gas tungsten arc welding was carried out using direct current straight polarity. These techniques resulted in a significant improvement in fusion zone hardness and tensile properties, which is attributed to reduced copper segregation and natural aging as well as aging caused by heat of multipass welding.