Now-a-days, Spot welds are used majorly in design. Spot welds are now not limited to only sheet metal works or say joining thin sheets. Higher thick plate would require more Amperage if spot weld is carried out by Resistance spot welding process. Also, Pressure applied & cycle time also increases for thicker plates. With advent of technology in the field of welding, solutions for such thing is not far way.
Arc Spot welding is the process development which answers all the concerns. By GTAW process Or by GMAW process, spot welding can be carried out. GTAW or TIG welding has been proven best for the fusion arc spot welding.
With the use of activated flux, one can achieve good penetration compared to conventional TIG welding process and thus higher thick plates can be joined with the ease with out compromising to the required Strength.
Process details and parameters in further blogs
Thank you
KP Bhatt
Weldknowledge 
Does mechanism of bonding in thick plate same as thin plate?
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As it is arc spot welding, arc will be initiated from one side and at anode spot metal would be heated up and molten pool is formed which will be produce digging action and thus two interface will get melted and fused together
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How GMAW process help in arc spot welding? Which mechanism act during GMAW process?
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It is same as GTAW process, only difference here is current is set on higher side and arc on time has to be controlled. One thing more is observed is as this process uses consumable electrode, metal build up is likely to happen.
Also, other technique you drill hole on upper plate, then with GMAW process fill up the hole. Here two plates must be kept tightly before welding. This is also called plug weld.
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what if spot darkens more by the time goes…does anything like this happens in arc spot welding?
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