Buj-Corral Irene, Domínguez-Fernández Alejandro, Gómez-Gejo Ana
Department of Mechanical Engineering, Escola Tècnica Superior d'Enginyeria Industrial de Barcelona (ETSEIB), Universitat Politècnica de Catalunya (UPC), Av. Diagonal, 647, 08028 Barcelona, Spain.
Materials (Basel). 2020 May 7;13(9):2157. doi: 10.3390/ma13092157.
Prostheses made from ceramic materials have the advantages of producing little debris and having good durability, compared with those made from metal and plastic. For example, hip prostheses require a porous external area that allows their fixation by means of osseointegration and a solid internal area that will be in contact with the femoral head. The manufacturing of complex ceramic shapes, by means of machining processes, for example, is complicated and can lead to breakage of the parts because of their fragility. The direct ink writing (DIW) process allows the printing of ceramic pastes into complex shapes that achieve their final strength after a heat treatment operation. This paper studies both the dimensional error and surface finish of porous zirconia prismatic parts prior to sintering. The variables considered are infill, layer height, printing speed, extrusion multiplier and bed temperature. The responses are the dimensional error of the lateral walls of the samples and an areal roughness parameter, the arithmetical mean height, Sa. Mathematical models are found for each response, and multiobjective optimization is carried out by means of the desirability function. The dimensional error depends mainly on the interaction between layer height and infill, while the roughness on the interaction between infill and printing speed. Thus, infill is an important factor for both responses. In the future, the behavior of compact printed parts will be addressed.
与由金属和塑料制成的假体相比，由陶瓷材料制成的假体具有产生碎片少和耐久性好的优点。例如，髋关节假体需要一个多孔的外部区域，以便通过骨整合实现固定，还需要一个与股骨头接触的实心内部区域。例如，通过加工工艺制造复杂的陶瓷形状很复杂，并且由于其易碎性可能导致零件破裂。直接墨水书写（DIW）工艺允许将陶瓷浆料印刷成复杂形状，这些形状在热处理操作后达到其最终强度。本文研究了烧结前多孔氧化锆棱柱形零件的尺寸误差和表面光洁度。考虑的变量有填充率、层高、打印速度、挤出倍数和床温。响应变量是样品侧壁的尺寸误差和一个面积粗糙度参数，算术平均高度，Sa。为每个响应变量建立了数学模型，并通过合意函数进行了多目标优化。尺寸误差主要取决于层高和填充率之间的相互作用，而粗糙度则取决于填充率和打印速度之间的相互作用。因此，填充率是两个响应变量的重要因素。未来，将研究致密印刷零件的性能。
