← Glossary

Lack of fusion

Insufficient root fusion leads to incomplete weld bonding and porosity. The risk of cracking increases.

Physical-Chemical Mechanism of Action

Reversion is the process by which metal re-establishes its chemical composition during cooling. If heat input is insufficient, this doesn't happen completely, leading to incomplete bonding and porosity.

Metallurgical Relevance & Welding Risks

Incomplete reversion can lead to cracks and fracture of the weld. The weld is softer and less tough, which impairs its mechanical properties.

Workshop Practice & Action Guidelines

Make sure heat input during welding is sufficient. Keep the temperature above the critical point until fully cooled. For high-grade steels and alloys, use controlled cooling.

MetallurgieSchweißtechnik

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