What polarity has electrons flowing from the tungsten to the work piece?

What polarity has electrons flowing from the tungsten to the work piece?

• A. AC
• B. DC+
• C. DC-
• D. Non-polar

Answer: (C)

The correct choice is based on the understanding of welding polarity, particularly in gas tungsten arc welding (GTAW) or TIG welding. In this process, the polarity known as DC negative (DC-) is where electrons flow from the tungsten electrode to the workpiece. In other words, the tungsten is negatively charged, and it emits electrons that move toward the positively charged workpiece during the welding process. This flow of electrons is crucial because it influences the heat concentration and arc stability. With DC-, the electron flow helps achieve a deeper penetration of the weld, which is often desirable for producing high-quality welds in various materials. The other polarities mentioned serve different functions: AC (alternating current) alternates the direction of electron flow, which can be useful in specific applications, especially when welding aluminum. DC positive (DC+) would mean the electrons flow from the workpiece to the tungsten, which is generally not used in processes where a controlled, focused arc is necessary. Lastly, non-polar does not apply in welding where polarity is a key aspect of the process. Understanding these principles is fundamental for selecting the right polarity for specific welding tasks.

The correct choice is based on the understanding of welding polarity, particularly in gas tungsten arc welding (GTAW) or TIG welding. In this process, the polarity known as DC negative (DC-) is where electrons flow from the tungsten electrode to the workpiece. In other words, the tungsten is negatively charged, and it emits electrons that move toward the positively charged workpiece during the welding process.

This flow of electrons is crucial because it influences the heat concentration and arc stability. With DC-, the electron flow helps achieve a deeper penetration of the weld, which is often desirable for producing high-quality welds in various materials.

The other polarities mentioned serve different functions: AC (alternating current) alternates the direction of electron flow, which can be useful in specific applications, especially when welding aluminum. DC positive (DC+) would mean the electrons flow from the workpiece to the tungsten, which is generally not used in processes where a controlled, focused arc is necessary. Lastly, non-polar does not apply in welding where polarity is a key aspect of the process. Understanding these principles is fundamental for selecting the right polarity for specific welding tasks.