Hob Cutters with a Nanosphere Coating
Long tool life and manufacturer quality after each conditioning
Thanks to the Nanosphere coating, the new LMT hob cutter can ensure a real surge in performance. They can achieve up to a 30 percent longer tool life than tools with conventional aluminium chrome nitride coatings – and at considerably higher cutting speeds. Thanks to the patented Nanosphere procedure, LMT can guarantee the reconditioning of the hob cutter to the quality of a new tool over their entire lifecycle.
- The new Nanosphere coating in the microspcopic view: The multi-layer design of the hub cutter is responsible for a better thermal insulation, and its elasticity prevents the coating from chipping
High levels of stress from the increasing use of dry hobbing and interrupted cutting in particular can cause cracks to appear in conventional coatings, thereby reducing tool life. Application engineers and experts from LMT Fette and Boehlerit, the Institute of Manufacturing Technology and Quality Management at the University of Magdeburg spent ten months working on their own tailor-made coating to solve these issues. The multilayer coating of the Nanosphere hub cutter prevents microcracks “running” unhindered through the basic material, which causes flaking of the coating in conventional, single-layer coatings. Such stresses are redirected within the multilayer coating and absorbed in the upper layers. The cutting edges stay stable as a result. The multilayer structure of the Nanosphere coating also ensures better heat insulation - it takes longer for the tool steel to be heated up by the high temperatures generated by the hobbing process. At the same time, Nanosphere prevents the “eggshell effect” thanks to its multilayer structure. In conventional hob cutters, the HSS steel becomes soft at extreme temperatures, but the coating stays hard and then flakes off like an eggshell. This is not the case with Nanosphere: as soon as the substrate loses stability and yields under stress (a process that occurs on a microscopically small scale), the flexible multilayer coating layer also yields. This prevents the hub cutter coating from dissolving from the substrate and cracking. The result is a considerably longer tool life.
- A microscopic look at the new Nanosphere layer: The multilayer structure ensures better heat insulation and prevents the coating flaking off thanks to its elasticity.
The reconditioning of a hob cutter to manufacturer quality is equally important. The customer must be ensured of the reconditioned tool’s consistent quality over its entire lifecycle. The relative increase in performance is not the only factor here. In modern production systems, the principal factor is process reliability. The new multilayer coating meets these requirements exactly. Firstly, very frequent re-coating to original quality is possible, and, secondly, the overall reconditioning costs are reduced as the new multilayer coating can be directly applied again in the initial cycles after the cutting face has been ground.
Nanosphere