This paper investigates thermal modelling of the selective laser sintering process for amorphcus

polycarbonate powders. The aim is to develop a simulation for process accuracy and control which are key areas of developement for the new layer manufacturing rapid prototyping technologies. A state-of-the-art adaptive mesh 20 finite difference code is used simultaneously to consider heating and sintering and its results compared with a classical moving heat source model and with experiments. The analysis shows that the change of material thermal properties with temperature and particularly with position as densification takes place must be included for accurate prediction of both densification and of the phenomenon known as 'bonus 2'. The work forms a basis for moving to a 3D simulation.