Maximum Hardening Depth
The maximum hardening depth is the zone in the base material that gets hardened by welding. It influences the hardness and strength of the material.
Physicochemical Mechanism of Action
The maximum hardening depth results from the thermal cycle during the welding process. As the material cools below the critical temperature (Tc), martensite forms, a highly hardened microstructure.
Metallurgical Relevance & Welding Risks
Too much hardening depth can lead to increased hardness and brittleness, which affects the mechanical load capacity of the material. This can cause cracks or fractures in the base material. Additionally, excessive hardening can contaminate the weld metal itself and reduce its toughness.
Workshop Practice & Procedures
To control the maximum hardening depth, it's important to carefully plan the cooling steps of the welding process. This includes choosing the right welding process and maintaining the correct temperatures and times. For steels with high carbon content, controlled cooling is especially important to ensure uniform hardening.