Excess weld metal
Filler metal excess is the surplus weld metal that protrudes beyond the specified dimensions on the top or bottom of a butt weld. This causes unnecessary notches and increases weight.
Physicochemical Mechanism of Action
Filler metal overfill occurs when more metal is melted during the welding process than necessary. This can be caused by excessive heat input or too slow cooling. The excess metal forms on the edges of the butt joint and protrudes beyond the intended size.
Metallurgical Relevance & Risks in Welding
Filler metal overfill can lead to several problems. It increases the weight of the component, which is particularly significant in heavy machinery or structures. Furthermore, it can cause unnecessary notches that damage the weld and reduce the service life of the joint. In extreme cases, the overfill can lead to cracking or spalling.
Workshop Practice & Instructions
To avoid filler metal overfill, it is important to precisely control the heat input and cooling rate. The heat input should be set so that only the necessary metal is melted. Cooling should be fast and uniform to keep the filler metal within the butt joint. If necessary, a weld metal with lower stress deformability or a special filler can be used to minimize the occurrence of overfill.