Heat Treatment

Hot forging provides workpieces with their geometry. The final component properties, such as strength, toughness, machinability and grain homogeneity, are achieved by hot forging and subsequent heat treatment. An optimum combination of properties as required for the particular application is attained by the special types of heat treatment.  

 

  • Normalizing
    This is used to obtain an even and fine-grain structure.

  • Quenching and Tempering
    This is a heat-treatment process which involves hardening and tempering in order to achieve a predetermined strength value while attaining high levels of toughness

  • Case Hardening
    This heat-treatment process is used on ready-for-assembly machined parts. The surface of the part is enriched with carbon before being hardened and tempered. Following this, the surface demonstrates a very high level of hardness compared to the core. The surface has low wear properties and is hard, whereas the core is very tough and resistant to stress (possible applications in shafts, gears and axles)

  • Soft Annealing
    This refers to the process of reducing the hardness of a workpiece to below a given value, e.g. for subsequent cold forging. During this process, the lamellar pearlite is spheroidized, which provides the steel with the lowest possible hardness.

  • Treating for Strength
    An annealing process for abtaining a certain tensile strength.

  • Treating for Ferrite-Pearlite Microstructure
    An annealing process for achieving a certain grain structure. Besides improving machinability, this heat treatment causes a reduction in the distortion behaviour of ferrite-pearlite grain structures during case hardening carried out subsequent to machining.

  • Controlled Cooling from the Forging Heat
    For certain parts, the required properties may be obtained by means of controlled cooling from the forging heat. Micro-alloy dispersion-hardening steels, for example, are particularly suited to this type of process.