Laser surface hardening
Laser surface hardening heats the surface locally and hardens it by self-quenching. It avoids deep heat treatment and increases strength and toughness.
Physicochemical Mechanism of Action
A laser beam focuses the energy on a small area of the material surface. This leads to fast local heating, while the depth of heat influence stays limited. The self-cooling of the surface then sets the hardening scale.
Metallurgical Relevance & Welding Risks
Laser surface hardening increases the strength and toughness of the surface without deep heat treatment. This prevents cracking and improves the behavior under mechanical load. However, inaccurate focusing or too short a hardening time can lead to incomplete hardness, which can make the surface softer.
Workshop Practice & Instructions
Use a focused laser beam for local heating of the material surface. Pay attention to precise focusing and a sufficient hardening time (in seconds). The specific parameters like energy input and duration vary with the material, but typically the hardening time is between 0.1 and 1 second. Always monitor the temperature curve and adjust the parameters accordingly.