High Brightness Laser Thick Section Cutting

Industrial Photonics

High Brightness Laser Thick Section Cutting

Introduction

Thick section cutting is an important production process in heavy industry, such as the shipbuilding, construction and nuclear industries. The excessive heat loss of bulk materials in the cutting process, alongside other factors such as operation skills and equipment limitations, means that thick section cutting can only be operated at low speed, and that the cut qualities usually involve kerf taper, high surface roughness and low tolerance. All of these issues make thick section cutting a difficult and expensive job.

Nowadays, traditional machining technologies cannot meet the current high demands in production rate and quantity.

Conventional laser thick section cutting plays an increasingly important role, however, there are still two main problems. Firstly, thick material can be difficult to penetrate rapidly with the laser beam, and the details of the thick section cutting mechanism and the method for obtaining the optimum cuts are not known. Secondly, thick materials can be very heavy and difficult to move, especially for ship yards and some dismantling works. Mobile laser thick section cutting technologies could solve these problems.

Aims

To investigate thick section cutting of aluminium, stainless steel and mild steel using fibre and disk laser systems (1µm laser source).
To investigate the benefits of side-jet cutting of aluminium and stainless steel using the disk laser (1µm laser source).
To understand the laser oxygen thick section cutting (LOTSC) process.
To investigate the laser oxygen thick section cutting (LOTSC) process by using both 1µm and 10µm laser sources.

Current Progress

Experimental

Cutting experiments of various thicknesses of aluminium, stainless steel, and mild steel have all been completed. Full cutting process characterisation for thin and thick section metals was carried out using high brightness 1µm laser sources.

Theoretical

A cutting model has been established that develops full fluid phenomena for melt ejection.

Publications

Articles

Sparkes, M., Gross, M., Celotto, S., Zhang, T. and O'Neill, W. (2008) Practical and theoretical investigations into inert gas cutting of 304 stainless steel using a high brightness fiber laser Journal of Laser Applications, 20 (1). pp. 59-67. ISSN 1042-346X.

Conference Papers

Zhang, T., Sparkes, M.R., Gross, M. S. and O'Neill, W. (2008) The studies of laser oxygen thick section cutting using disk laser In: 3rd Pacific International Conference on Application of Lasers and Optics (PICALO 2008), 16-18 April 2008, Beijing, China.
Sparkes, M.R., Gross, M.S., Celotto, S., Zhang, T. and O'Neill, W. (2006) Inert cutting of medium section stainless steel using a 2.2kW high brightness fibre laser In: International Congress on Applications of Lasers & Electro-Optics (ICALEO 2006), 29-31 October 2006, Scottsdale, AZ, US.
Sparkes, M., Zhang, T., Rand, C., Celotto, S. and O'Neill, W. (2005) Application of a high brightness Yb Fibre laser in high speed cutting of C-Mn sheet steel In: International Congress on Applications of Lasers and Electro Optics (ICALEO 2005), 31 Oct - 3 Nov 2005, Miami (FL), USA.

Presentations

O'Neill, W., Gross, M.S., Sparkes, M.R. and Zhang, T. Analysis of disc and yb laser cutting of metals In: Proceedings of LaserSys, 24 March 2008, Stuttgart, Germany.
O'Neill, W., Sparkes, M.R.. Gross, M.S. and Zhang, T. High brightness cutting and welding In: Association of Laser Users (AILU) Workshop: Advances in Lasers and Beam Delivery Enabling New Industrial Applications, 12 December 2007, Cambridge, UK.
Sparkes, M.R., Zhang, T., Celotto, S., Gross, M. and O'Neill, W. Cutting with fibre lasers In: AILU Workshop: Fibre Lasers: the Future of Laser Materials Processing Technology, 8 March 2006.

Photography Competition Entry 2007

An photograph taken during work on this project was highly commended in the Owlstone Photography Competition at the Department of Engineering in 2007:

http://www.eng.cam.ac.uk/photocomp/2007/tz222_1.shtml