← Glossary

Brazing Filler Wetting Angle

The solder joint wetting angle is the angle at which molten solder forms on a metallic surface. A smaller angle indicates better wettability and higher affinity.

Physicochemical Mechanism of Action

The solder is repelled from the surface when it is in thermodynamic equilibrium. The angle is set by the tension between the melting solder and the solid surface.

Metallurgical Relevance & Welding Risks

Too large an angle can degrade the joint, because the solder wets the surface poorly. That can lead to pores and low strength. Too small an angle, on the other hand, causes overrun and clogging of the joint.

Workshop Practice & Instructions

For the best soldering results the wetting angle should be between 30° and 45°. You can control this by choosing the right solder and the right temperature.

MetallurgieSchweißtechnik

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