Red Seal Metal Fabricator (Fitter) Practice Exam

What is the purpose of applying a filler metal in welding?

1. To coat the surface of the metal

2. To join two metals together by adding additional material

3. To prevent oxidation during welding

4. To enhance the appearance of the weld

The correct answer is: To join two metals together by adding additional material

The purpose of applying a filler metal in welding is primarily to join two metals together by adding additional material. When two pieces of metal are to be welded, the filler metal is used to create a strong bond between them, effectively filling the gap and enabling the formation of a robust joint. The filler metal, once melted, combines with the base metals to form a cohesive weld pool that solidifies into a joint that has structural integrity and strength. In welding processes such as MIG (Metal Inert Gas) or TIG (Tungsten Inert Gas), the filler metal not only aids in bonding the metals but also ensures that the weld area can withstand stresses and loads similar to or better than the base metals themselves. Therefore, the role of the filler metal is integral to achieving quality welds that meet necessary mechanical and structural specifications.