What is the term for the part of the groove face located at the joint root?

The correct answer is "Root face," which refers to the area at the joint root in a groove weld. The root face is specifically the surface of the groove that is adjacent to the edges of the base metal being joined. It is critical to understand the root face as it plays a significant role in weld quality and penetration. The characteristics of the root face can influence how effectively the welding arc can penetrate into the joint and form a strong bond between the two pieces of metal.

Understanding the root face is essential for welders because it helps in determining the proper welding technique, settings, and preparation needed for achieving a successful weld. Ensuring that the root face is clean and properly aligned can help prevent defects such as undercutting or incomplete fusion.

The other terms, while related to the welding process, do not accurately describe the part of the groove face at the joint root. The root edge is typically the very edge of the root area, whereas the base face and joint face refer to different aspects of how the two pieces of metal interface and connect, which is outside the specific definition of the root face.