This paper reports on a numerical and experimental investigation of laser drilling of tungsten alloy for modeling the temperature distribution to predict the heat affected zone (HAZ) and the shape of the hole. The numerical method is based on the solution of the integral form of the thermal energy equation, expressed in terms of temperature via corresponding constitutive relation, and discretized by the finite volume method. The method has been applied to a number of test cases and the results are compared with the experimental data. It was observed that the finite volume method results were in good agreement with experimental data and that it can be used as useful tool for predicting heat affected zone and the shape of the hole during laser drilling process. © 2015 The Authors. Published by Elsevier Ltd. Peer-review under responsibility of DAAAM International Vienna.

Laser beam machining (LBM) is one of the most widely used thermal energy based non-contact type advance machining process which can be applied for almost whole range of materials. This paper defines mathematical models for surface roughness prediction (Ra, μm) and width of heat affected zone (HAZ, mm) during laser cutting of alloy steels 1.4571 and 1.4828 with nitrogen as assist gas. For defining appropriate mathematical models multiple regression analysis is used with four independent variables. Following parameters are varied: cutting speed, focus position, nitrogen assist gas pressure and stand-off. Obtained mathematical models describe dependence of Ra and HAZ from varied process parameters. © 2014 The Authors. Published by Elsevier Ltd. Selection and peer-review under responsibility of DAAAM International Vienna.