Product Code: ICA10_M804

Laser Scribing of Stainless Steel with and Without Work Media
Authors:
Anna Unt, Lappeenranta University of Technology, Laser Processing Technology Research Group, Faculty of Technology; Lappeenranta Finland
Heidi Piili, PRESENTER NOT AUTHOR, Lappeenranta University of Technology, Laser Processing Technology Research Group, Faculty of Technology; Lappeenranta Finland
Marika HirvimäKi, Lappeenranta University of Technology, Laser Processing Technology Research Group, Faculty of Technology; Lappeenranta Finland
Matti Manninen, Lappeenranta University of Technology, Laser Processing Technology Research Group, Faculty of Technology; Lappeenranta
Antti Salminen, Lappeenranta University of Technology, Laser Processing Technology Research Group, Faculty of Technology; Lappeenranta Finland
Presented at ICALEO 2010

The advantages such as tight restrictions for heat and mass transfer make micro/milli scale devices of mixing and droplet formation viable to become widely used in specialty chemical industry. Small dimensions and simple geometry ensure laminar flow and mixing through diffusion, ensuring well-defined behavior of mixing and short reaction times. Combining dry etching by laser beam with wet chemical etching is expected to reduce the production costs of these novel devices.

In this study the manufacturing of grooves in stainless steel SS316 L by means of laser micro/milli processing was investigated. Deep and narrow channels with depth to width ratio of 1:1 at least are preferable, width is allowed to vary from 10-500 micrometer. Lasers used for this study were: 5 kW IPG YLR-5000 S, 200 W IPG YLS-200-SM-WC, 1 kW IPG YLR-1000-SM fiber lasers, 400 W Powerlase diode pumped Nd:YAG laser and Nd:YVO4 laser. Chemical assisted laser scribing is also included in this study.

Preliminary results show possibility to obtain channels with desired parameters in pulsed mode laser machining. However, investment cost for CW lasers are in order of magnitude smaller than for pulsed lasers, thats why the study was essentially focusing on lasers operating in CW mode. Optimal scribing parameters were defined by adjusting laser power, number of repetitions and speed. Preliminary experiments done without any media resulted in low quality grooves with moderate depth and burned edges. It was concluded in this study that finding a suitable chemical to improve to scribing process is a key moment of getting channels with acceptable quality.