a Dpto.F !ýsica Aplicada,Uni v ersidade de Vi g o,La g oas Marcosende 9,E-36200 Vi g o,Spain b Department ofEn g ineerin g ,Laser En g ineerin g Group,The Uni v ersity ofLi v erpool,Brownlow Street, Li v erpool,L69 3GH,UK
Received 3 May 2001;received in revised form 24 July 2001;accepted 24 August 2001
Abstract Slate is a natural stone which has the characteristic that shows a well-developed defoliation plane,allowing to easily split it in plates parallel to that plane which are particularly used as tiles for roof building.At present,the manufacturing of slate is mostly manual,being noisy, powdery and unsafe for the worker.Thus,there is a need to introduce new processing methods in order to improve both the working conditions and the quality of the products made of slate. Following the previous work focused on the drilling and cutting of slate tiles using a Nd:YAG laser,we present in this paper the results of the work carried out to explore the possibilities to cut slate plates by using a CO2 laser.A 1.5 kW CO2 laser was used to perform di .erent experiments in which,the in .uence of some processing parameters (average power, assist gas pressure)on the geometry and quality of the cut was studied.The results obtained show that the CO2 laser is a feasible tool for a successful cutting of slate.© 2001 Elsevier Science Ltd.All rights reserved.