Flamelämpökäsittely

Flamelämpökäsittely, often translated as flame heat treatment or flame hardening, is a surface hardening process used to increase the wear resistance of ferrous metals, particularly steel. It involves rapidly heating the surface layer of a component to a specific temperature using a high-intensity flame, typically from an oxy-fuel gas torch. Immediately following the heating phase, the surface is rapidly cooled, usually by a water quench.

The process creates a hard, shallow case on the surface of the metal while leaving the core relatively soft and ductile. This contrast in properties is crucial for applications requiring a strong, wear-resistant surface combined with toughness to absorb shock and prevent brittle fracture. The depth of the hardened case can be controlled by factors such as flame intensity, heating time, and the speed of flame travel.

Flamelämpökäsittely is an economical and efficient method for hardening localized areas of components. It is often applied to parts like gears, camshafts, crankshafts, and wear plates. The equipment required is relatively simple, making it suitable for both mass production and repair work. The process is also relatively fast compared to some other heat treatment methods. However, it requires careful control of temperature and cooling rates to achieve the desired metallurgical structure and hardness. Distortion can be a concern, and techniques are employed to minimize it.