Which of the following is a characteristic of direct current in gas metal arc welding?

In gas metal arc welding (GMAW), direct current (DC) is known for providing a smoother and more stable arc, which is essential for effective welding. This stability allows for better control over the weld puddle, making it easier to achieve a clean and consistent weld bead. The direct current creates a strong and continuous arc, which minimizes fluctuations that can lead to weld defects or inconsistencies.

Furthermore, the characteristics of DC make it particularly suitable for different welding applications, including welding various types of metals. In contrast, options regarding lower heat input or efficiency are not specific advantages associated with direct current; instead, they depend on several factors, including welding settings and materials. While aluminum can be welded with DC, it is typically more associated with alternating current (AC) for certain processes due to the nature of aluminum's electrical conductivity. Thus, the smooth and stable arc provided by DC is a defining feature in gas metal arc welding, leading to better results in the final weld quality.