Weldability and weld suitability
The weldability of the components to be joined essentially depends on the influencing variables “material”, “design” and “production”. These three influencing variables are to be determined in more detail with regard to their properties. In the case of the material, this is the welding suitability, in the case of the design, the weld safety and in the case of the production, the welding possibility. For weldability, these three properties or influencing variables are of approximately equal importance. Especially in resistance welding, the assessment of weldability is of great importance. Here are the most important criteria for this.
In the case of the material, the chemical composition, the metallurgical properties, the surface condition and the general physical properties have a significant influence on the welding suitability. Primarily decisive for the welding suitability are the electrical conductivity, the melting temperature and the thermal conductivity as physical properties of a material. In terms of surface finish, it is the roughness, impurities and coatings of the material that directly influence welding suitability.
In the field of metallurgy, the grain size, inclusions in the material, the microstructure formation and the transformation behaviour have an effect on the welding suitability. The strength, the hot cracking tendency, the ageing and the behaviour of the melt during solidification are decisive for the welding suitability with regard to the chemical composition.