← Glossary

Interpass lack of fusion

Defective bonding between successive weld beads within a multi-run weld, often caused by inadequate slag removal or incorrect amperage.

Interpass lack of fusion occurs when the individual weld bead doesn't fuse cleanly with the one underneath. This usually happens when you don't remove slag or scale properly. The result is voids and weak spots in the weld that can crack under load. So make sure to thoroughly clean each layer and keep the weld clean, then you'll get a homogeneous joint.

MetallurgieSchweißtechnik

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