Quenched and tempered hardness evaluation
Tempered hardness evaluation measures the core hardness of a part after quenching and tempering to make sure it meets the tensile strength target. It's a direct indicator of strength.
Physico-chemical mechanism of action
Hardening hardness evaluation refers to determining the hardness of the component core after welding. This is done by measuring the force required to deform a certain indentation in the material. Hardness correlates directly with tensile strength and indicates how resistant the material is to mechanical stress.
Metallurgical relevance & welding risks
Insufficient hardening hardness can lead to cracks and fractures in the component. This can cause safety issues and increased component failure. Too high a hardness can make the material susceptible to hot cracking, as it becomes glass-hard during rapid cooling.
Workshop practice & instructions
For a correct hardening hardness evaluation, it is important to perform the hardness measurement directly after quenching and tempering. The measurement should be taken at least 24 hours after welding to ensure the material has fully cooled. Use a robust hardness tester with high precision and follow the manufacturer's instructions exactly. The measured hardness should be within the specified range to guarantee the desired strength.