Surface Roughness Influence
Rough surfaces cause more friction and can impair welding by hindering fluid flow or splitting the arc.
Physical-Chemical Mechanism of Action
Rough surfaces have microscopic height differences that enlarge the contact area between metal and welding filler. This increases friction and can lead to uneven stress distribution.
Metallurgical Relevance & Welding Risks
Roughness can cause the welding filler to not spread evenly on the surface. This can lead to porosity, distortion, or even wear of the weld joint. Additionally, the rough surface can alter stress distribution in the metal, potentially causing hot cracks or other mechanical defects.
Workshop Practice & Action Guidelines
To minimize the negative effects of surface roughness, you should polish or smooth the surface before welding. For high-precision applications, use special polishing agents and ensure uniform treatment. For heavily rough surfaces, it may be helpful to use an additional protective layer to improve the contact area.