Heat & Surface Treatment

We can offer you a wide range of hardening and surface treatment processes

Heat Treatment

The full range of heat treatments - in Germany, Czech Republic, India and in China.

The term martensitic hardening refers to a heat treatment process consisting of austenitization and cooling under conditions that produce an increase in hardness through the more or less complete transformation of austenite into martensite.

Austenitization is the treatment step in which the workpiece is brought to the austenitizing temperature and full phase transformation and carbide dissolution change the matrix of the steel to austenitic.

Austenitization is followed by the cooling step. To ensure that the entire workpiece assumes a martensitic structure, the speed of the temperature drop must be greater than the critical cooling rate of the particular steel.

Cooling can be carried out in a range of different media characterized by their cooling effects in the different temperature ranges.

The use of abrasive yarns such as polyester semidull or elastane presents major problems for traditional standard sinkers. They very quickly cut into the jack area of the sinker, producing a deep groove. This has an enormous impact on the quality of the fabric. Classic error patterns such as strips, irregular stitching patterns or even capillary breaks are unavoidable.

And the consequence: the machine must be completely refitted – at very short intervals. Not only does this drive the cost of spare parts up, but frequent downtime also reduces your all-important productivity levels.

These special sinkers feature substantially increased hardness, particularly in the heavily stressed jack area, considerably extending their service life.


  • Less idle time
  • Reduced costs
  • Increased productivity
  • Optimum machine quality

The use of this technology is not limited to this particular example. The technology is also available for special components that are partially hardened in order to meet high wear requirements. Because the heat input is low, the hardening is produced by "self-quenching" – and ´there is no distortion.

KERN-LIEBERS Textile uses a powerful special hardening process to achieve an extremely high level of surface hardness in our products. The surface is then characterized by a very high level of wear resistance. The elastic properties of the raw material are retained. This manufacturing process can be used on components from a sheet thickness of 0.2 mm.