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Objective: To investigate parameters of laser for slurry-based selective laser sintering of ZrO2 toughened Al2O3 ceramics for dental restoration.Methods: The surface temperature of one layer of zirconia-toughened alumina(ZTA)ceramics was tested by infrared thermal imager with different laser processing parameters(off focus distance,laser power and scanning speed).The microstructure of the layer was observed under scanning electron microscopy(SEM).Then the appropriate parameters of laser was used for forming green parts,and the green parts were prepared by self-developed dental ceramic rapid prototyping equipment and the green parts was sintered under the temperature of 1200℃.After that,linear shrinkage,relative density,apparent porosity measurement,three-point bending strength were measured and the microstructure of cross-section was observed by SEM.Results: With off focus distance of 20mm,scanning speed 500mm/s,laser power 10W,the top and bottom surface temperature of the layer was 236℃±3.18MPa,237±1.23MPa.The linear shrinkage was 0.20%±0.03%,relative density was 51.91±4.63%,apparent porosity was 46.86%±2.54%,bending strength was 27,89±3.01MPa.Conclusion: The off focus distance and scanning speed are the main factors affecting the surface temperature of ZTA composite ceramic layer.Through reasonable parameter of laser technology,the layer can be bonded well with each other,and we can even get the dental ZTA ceramics layer with a controllable micro morphology.The specimen shows no significant transformation after 1200℃ semi-sintering,and the three points bending strength could also meet the operation requirement for the glass infiltrating.