With the introduction of the Euro 7 emission standard, the particulate matter values for all new motor vehicles are to be drastically reduced-regardless of the type of drive. This means that the focus is also increasingly on brake systems. The solution here is brake discs with low-wear hard coatings, because less wear means less particulate matter. Against this background, NAGEL Maschinen- und Werkzeugfabrik GmbH is expanding its portfolio to include systems for brake disc coating.
The core modules for applying hard coatings to brake discs-usually cast brake discs are a laser cell, which operates according to the high-speed LMD process, and a double-sided surface grinding machine for finishing. The laser coating machine from NAGEL allows workpiece changeover times of less than two seconds, meaning that the powder flow, which is fundamentally sensitive to pressure fluctuations and acceleration, does not have to be interrupted. Powder efficiencies of over 94% were measured in the coating process.
The double-sided surface grinding machine used by NAGEL offers high rigidity, which enables precise and reproducible machining. The machine processes brake discs with an outer diameter of up to 450 mm. Depending on the coating system and customer requirements, the Nagel Group has a solution. For example, a typical midrange brake disc can currently be ground on both sides in approx. 50 seconds. Where required, a specially developed noncontact air measurement system monitors the machining process in operation.
The time-critical ramp-up of the coated brake disc (according to the current status, from July 1, 2025) requires intensive networking of the disciplines of coating and grinding. Hans-Peter Böhm, Head of Development for Coating Systems, explained: "The qualification of the coating system must be accompanied in parallel by material-related tests on several levels. In order to be fast, an overall process responsibility with short control loops is necessary, which NAGEL can provide together with the group's own cutting material supplier Elgan Diamantwerkzeuge GmbH & Co. KG."
In addition to process development for a wide range of hard material coatings, including grinding, NAGEL will soon also be offering options for the production of coated brake discs for homologation at its Nürtingen, Germany, plant. The prototype systems already available will be expanded with corresponding series systems in the second quarter of 2023.
In addition, material and powder analysis facilities, geometry and surface measuring equipment, as well as a scanning electron microscope for evaluating micrographs to check the results, are available for process development. Dr Claus-Ulrich Lott, Managing Director at NAGEL, explained: "The aim is to bundle our coating, grinding and quality expertise in a competence center for brake discs. Since we have group-owned production operations for abrasives, we are able to optimize the entire process very quickly and tailor it to specific customer needs. At its core, it is all about the lowest unit costs. One of the decisive points is to achieve the lowest possible grinding allowance in the very expensive wear layer, and here the laser technology used has a decisive influence. It is possible, for example, to achieve a grinding allowance of less than 100 micrometers."
NAGEL's delivery options include the entire process: the processing lines with laser cladding coating systems, equipment for powder handling, extraction, cooling, double-sided grinding machines with coolant preparation, tool systems and a wide variety of measuring and monitoring systems for process control.
"When it comes to noncontact measuring, NAGEL draws on its experience in fine and ultra-fine machining," said a company spokesperson. "Especially where the highest qualities are required, such as in honing or finishing, high-precision monitoring systems are sometimes part of the standard equipment of the machines."
NAGEL also supplies individually tailored automation concepts with line interlinking or suitable robot solutions, and the modular design makes it possible to scale the systems easily and quickly to different outputs. Machine production and the merging of peripheral components as well as customization are carried out under one roof at the main plant, meaning that customers have access to the specialists in the competence center and the existing systems for process optimization of their series systems or also for developments.
Authored by NAGEL
For more information contact:
Nagel Precision, Inc.
288 Dino Drive
Ann Arbor, MI 48103
734-426-5650
info@nagelusa.com
www.nagelusa.com