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inspire AG, Tannenstrasse 3, CH-8092 Zurich
Laser processing of cutting tool inserts using ultrashort laser pulses
Process and parameter set development
Introduction
Technology
Application
Results
Status
Partners
Contact
January 2012
Manufacturing of cutting tool inserts by laser technology has been done in recent years mostly with short pulse lasers with pulsewidths in the range of nanoseconds and high average powers in order to be able to cut through rather thick materials up to multiple millimeters. In this study a laser system with a pulsewidth of a few picose-conds is used to analyze laser - material - interaction which is athermal to large parts of the processing cycles. Keeping up good processing times at the same as quality aspects are improved are the key contents of this project. Surface roughness, cutting edge radius and process parameter optimization are planned. The market for this type of technology in is yet fairly small but tends to have a large potential in future years as a replacement for grinding.
This application involves the use of a pulsed laser source with pulsewidths in the range of about 10 picoseconds. Therefore the process is on the verge of cold ablation which is an essential condition on processing of diamond substrates without major graphitization. Laser beam guiding to the workpiece is radial and tangential. Different polarization states, beam shaping, process gases and vario-us burstmode designs are applied and analyzed. Especially a burst mode with flexible pulse bursts which enable to increase processing times as well as surface characteristics at the same time are under consideration. Structural defects and heat influence is analyzed in detail.
The approach can be used on cutting tool insert as well as rotary tool geometries. Base material are blank polycry-stalline diamond structures on a carbide substructure. A particular advantage of this process strategy compared to grinding is the geometrical flexibility in terms of tool design while improving processing time and edge quality.
In total this project has a two year duration in terms of a bilateral project which has started in January 2011. The first work packages have been successfully completed. These are process analysis, optimization of surface rough-ness parameters and beam guiding strategies.
Surface roughness reductions on the flank face as well as defining parameters to control cutting edge radius development have been achieved. Especially beam guiding in terms of hatch design strategies have been carried out. Further investigations tend in the direction of further improvements on minimal cutting edge radius properties and on novel beam guiding approaches.
EWAG AG: Grinding and laser machine manufacturer.
MSc Mech. Eng. ETHZ Claus Doldinspire AGTechnoparkstrasse 1 / PFA H43CH-8005 Zurich
Tel +41 44 633 7956email [email protected]