正交试验法优化挤出3D打印水溶性盐芯的成形精度OA

Water-soluble salt cores were fabricated by extrusion 3D printing technology and stepwise sintering process using the inorganic salt sodium carbonate(Na2CO3)and sodium chloride(NaCl)powders as matrix materials,the polyvinylpyrrolidone(PVP)as binder,the ammonium polyacrylate as dispersant,and the anhydrous ethanol as solvent.Taking the extrusion nozzle inner diameter,the layer height-to-extrusion nozzle inner diameter ratio,the printing speed and the infilling direction as four critical factors,a four-factor,three-level orthogonal experiment was carried out,and optimal printing parameters were obtained through measuring the surface roughness and dimensional shrinkage rates of the water-soluble salt cores fabricated by the extrusion 3D printing technology with different process parameters,and determining the influence order of priority of different printing parameters on the forming precision of the water-soluble salt cores by using of range analysis.The results show that the extrusion nozzle inner diameter and layer height-to-extrusion nozzle inner diameter ratio are the dominant factors affecting forming accuracy of the water-soluble salt cores.Under the optimal printing conditions of extrusion nozzle inner diameter of 0.51 mm,layer height-to-extrusion nozzle inner diameter ratio of 70%,printing speed of 600 mm/min and infilling direction of 45°,the obtained salt cores possess better forming accuracy,with a surface roughness of 49.67 μm and dimensional shrinkage rates of 17.49%in the X direction and 18.32%in the Z direction.