Ceramic components manufacturing by selective laser sintering

Autores: Bertrand, P.|Bayle, F.|Combe, C.|Goeuriot, P.|Smurov, I.
Fuente: Applied surface science
en prensa
2007

In this present paper, technology of Selective Laser Sintering/Melting is applied to manufacture net shaped objects from pure Yttria-Zirconia powders. Experiments were carried out on a PHENIX SYSTEMS- PM100 machine with a 50 W fibre laser. Powder is spread by a roller over the surface of a 100 mm diameter alumina cylinder. Design of experiments has been applied to identify influent process parameters (powder characteristics, powder layering and laser strategy) to obtain the best ceramic component quality (density and structure). The influence of the Yttria-Zirconia particle size and morphology onto powder layering process has been analysed.The influence of the powder layer thickness on laser sintering-melting was studied for different laser beam velocity V (V=1250-2000 mm/s), defocusing length (-6 to 12 mm), distance between two adjacent vectors (20 to 40 µm), vector length and temperature of the furnace. The powder bed density before the laser action is also reported to have significant influence on the density of the manufactured samples. Different lasing strategies were applied and compared: different laser beam scanning paths to fill the sliced surfaces of the manufactured object, variation of laser length lines (so called ?vectors?), for different strategies of powder layering, temperature of the furnace and post heat treatment in conventional furnace. Performance and limitations of different strategies are analysed applying the following criteria: geometrical accuracy of the manufactured samples, porosity. The process stability was proved by the fabrication of a 1cm3 volume cube.