Poor ripple
Scalloping is an uneven surface of the weld bead, caused by unstable arc conditions or uneven travel speeds. It leads to poor surface quality and increases the risk of corrosion.
Physical-chemical Mechanism of Action
Scale irregularity results from uneven travel speeds or unstable arc conditions during welding. This leads to uneven deformation and cooling of the weld, which in turn results in a rough surface profile.
Metallurgical Relevance & Risks in Welding
A scaly surface can be prone to corrosion, as it provides sites for hydrogen and other corrosive agents to attack. Additionally, the irregular surface can cause difficulties in assembly and further processing.
Workshop Practice & Instructions
To avoid scale irregularity, take the following measures:
• Stabilize arc conditions by maintaining constant current and voltage.
• Monitor travel speed and ensure it remains constant.
• Use high-quality shielding gas systems to avoid uneven cooling.