The electrode comes into direct contact with the workpiece, and some degree of force is applied Group of answer choices Electron Beam Welding (EBW) Gas Tungsten Arc Welding (GTAW) Resistance Spot Welding (RSW) Laser Welding (LBW) Plasma Arc Welding (PAW) Oxyacetylene Welding (OAW)

Gas Tungsten Arc Welding (GTAW) Resistance Spot Welding (RSW)

Explanation:

Only the Gas tungsten arc welding and the spot resistance welding have a physical electrode and both of them make a contact with the work-piece. Both of the techniques use a non-filling electrode that generates heat energy into the welding area of the work-piece. In the GTAW the tungsten electrode is brought directly into the contact of two closely spaced interfaces of the work-piece and the electric current generated by the arc produced and  the inert gas (usually argon) is used to shield the welding zone to prevent the oxidation of the material. A force of compressive nature is applied on the joint to keep the fused material at the joint to complete the welding. This welding process is also called Tungsten inert gas welding.

In the spot resistance welding the electrode comes into contact with the pieces of the workpiece (usually thin sheets upto 3mm) from both the sides of the workpiece and generates the heat of electric power without any spark intended. The filler material may be placed between the two joining pieces. This generates only the weld spots and not a continuous wekd seam.

In the other welding techniques the heat is generated via the non-solid energy beams such as electron beam in EBM, plasma in PAW, gas flame in Oxyacetylene welding.

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