Solidus surface
The solidus plane is the point in a thermal phase diagram below which a metallic alloy is completely solidified and no longer contains any melt. It indicates the temperature up to which the alloy remains stable.
Physicochemical Mechanism of Action
The solidus plane marks the transition from liquid to solid phase in a metal. Below this temperature, the material is fully crystallized and contains no free atoms or molecules that could move.
Metallurgical Relevance & Welding Risks
The solidus plane is crucial for the strength and hardness of the weld. When the material cools below this temperature, it can lead to a fine crystal structure, which increases toughness. However, too rapid cooling can make the material too hard and prone to cracking.
Workshop Practice & Action Instructions
To ensure the weld has a stable and tough crystal structure, the material should be cooled below the solidus plane. This can be achieved through controlled cooling or the use of cooling water. The exact temperature and time for cooling depend on the specific metal and the desired properties of the weld.