Comparison study: Cutting with the laser microjet© vs. well-established and new micro-machining technologies for applications of the watch industry Available to Purchase

Common cutting technologies for micro-machining are Electrical discharge machining (EDM), water jet cutting, dry ps-pulsed and fs-pulsed laser cutting. A newer technology for micro-machining so far is the Laser Microjet© technology which uses a ns-pulsed laser which is coupled into a water jet and by that guided to the work piece. In this paper all the above mentioned cutting technologies are compared applications in the watch industry. Two different geometries are cut with all the mentioned technologies for four different materials which are commonly used in the watch industry: maraging steel (Durnico), stainless steel, brass and CuBe. CuBe cannot be cut with ps-and fs-lasers because it is highly toxic and so is the vapor of CuBe. The paper compares the roughness on the kerf and the velocity of the processes. The roughness on the kerf is measured with the same white light interferometer and all data is treated in the same way to be able to achieve comparable results. The samples are cut by leading machining manufacturer for micro-machining systems: Makino - Electrical Discharge Machining, Rofin – fs-Laser cutting, water jet cutting – Dätwyler, Synova - Laser Microjet^© cutting, FH Bern - ps-Laser cutting) so that this paper can be considered as a state of the art study specific applications. The Laser Microjet^© cutting technology which uses a laser coupled into a water jet is not as well-known as other micro-machining technologies like dry laser cutting technologies, e.g. ps-and fs-laser cutting, or well-established technologies like water jet cutting or electrical discharge machining. This paper presents a comparison of those 5 cutting technologies for watch applications in terms of quality. The characteristic and the roughness of the kerf for the different technologies are compared. It will give an overview for different cutting technologies which are currently available on the market for watch applications.