In automotive manufacturing the environmental friendliness of vehicles is evaluated and regimented on the basis of concrete consumption and emission data. Manufacturers have to meet these requirements through increasingly complex technological systems, which need to work safely and reliably in all operating states regardless.
The engine control represents an approach with considerable potential. The innovative Camtronic system expands possibilities to influence the optimization of the combustion process through a load-dependent valve lift adjustment via a camshaft carrier with two moveable cam pieces. Depending on the driving profile, a reduction of fuel consumption of about 3.5 %–10 % is possible. Due to functional reasons the cam pieces of the Camtronic system are designed as a tubular component and comparatively thin walled. As a result, conventional processes for hardening reach their application limits because of its exercised strong heat load and the resulting component warping. The properties of laser hardening are virtually predestined for highly-stressed components with high functional integration, because, for example, compared to the induction hardening with comparable hardening depth it exercises a lower heat load on the component by up to 90 %.
The decision of the Daimler AG und the Steinbeis Transfer Center Laser Processing and Innovative Manufacturing Technology to develop the laser hardening on cam pieces together is based on positive experiences gained from former projects and the fact that the Steinbeis experts at the Pforzheim University already had sound know-how on regulated laser beam hardening. The implemented transfer project included proceeding fundamental feasibility studies as well as a precisely adapted process development for the application of laser hardening on the Camtronic cam pieces. The cooperation also contained implementation work for the introduction of the procedure into largescale production, including a processing concept for the subsequent production plant, the support on the realization of suitable hardening optics as well as the evaluation of the optics and other important plant components.
Subsequent to this project, which is awarded the Foundation’s Transfer Award – Löhn Award, the cooperation between the partners Daimler AG and Steinbeis is going to be continued with new applications for laser beam hardening in order to tap further potential with this new technology.
Prof. Dr.-Ing. Roland Wahl
Steinbeis Transfer Center Laser Processing and Innovative Manufacturing Technology, Pforzheim