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Incomplete Penetration

Defect where the weld metal fails to completely penetrate the joint root, thereby reducing the effective load-bearing cross-section.

Incomplete penetration means the weld hasn't properly fused into the root or joint bottom. Then only part of the weld cross-section carries the load, the joint is weakened and tears faster under load. Make sure you prepare the joint cleanly, hold the correct welding position, and don't move the arc too fast. Always check the root carefully, then you'll immediately see if the weld metal has properly fused through.

MetallurgieSchweißtechnik

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