Welding suitability of steel materials
As a general rule, materials with a low melting temperature and lower current and thermal conductivity are more suitable for welding than those with a high melting temperature and high current and thermal conductivity. Due to these properties, steel materials are considered to be well-suited for welding, which is also clearly proven in practice. Nevertheless, the chemical composition and metallurgical properties of the respective alloys must be taken into account.
Unalloyed and alloyed steels with an alloy content of more than 5% are suitable for resistance spot welding if neither excessive hardness nor hardness cracks occur without special measures. DVS leaflet 2902 Part 2 lists the spot welding suitability of the various steels according to ISO classification and can be used for information purposes.
Some alloys are classified as conditionally suitable due to their composition. It should also be noted that, for example, stainless chrome-nickel steels (stainless steel) have a higher electrical resistance as well as a lower thermal conductivity. As a result, they require a lower welding current and greater electrode forces when welding.
For further information, please refer to the DVS leaflets DVS 2902. Also notes on the setting values.