激光选区烧结成形涡轮叶片铸造用陶瓷铸型材料及浸渗强化工艺  

Laser Selective Sintering of Alumina-based Ceramic Molds for Hollow Turbine Blade Casting and Infiltration Strengthening Process

作　　者：周士翔 孙冬 陈双 陈安南[3] 闫春泽 史玉升[1,2] ZHOU Shixiang;SUN Dong;CHEN Shuang;CHEN Annan;YAN Chunze;SHI Yusheng(State Key Laboratory of Materials Processing and Die&Mould Technology,Ministry of Education,Huazhong University of Science and Technology,Wuhan 430074,China;Engineering Research Center of Ceramic Materials for Additive Manufacturing,Ministry of Education,Huazhong University of Science and Technology,Wuhan 430074,China;Department of Mechanical Engineering,City University of Hong Kong,Hong Kong 999077,China)

机构地区：[1]华中科技大学材料成形与模具技术国家重点实验室,武汉430074 [2]华中科技大学增材制造陶瓷材料教育部工程研究中心,武汉430074 [3]香港城市大学机械工程系,中国香港999077

出　　处：《精密成形工程》2024年第12期82-90,共9页Journal of Netshape Forming Engineering

基　　金：工业和信息化部“航空发动机与燃气轮机”国家科技重大专项(2017-Ⅶ-0008-0102)。

摘　　要：目的针对传统成形方法制备铝基陶瓷铸型加工周期长、难以加工复杂结构等问题,开发新的技术,以一体化制备复杂结构陶瓷铸型。方法采用激光选区烧结(Selective Laser Sintering,SLS)增材制造技术,一体化成形铝基型芯/型壳铸型。结果采用球形氧化铝粉体颗粒级配并添加少量气相氧化硅助流剂的方法,不仅提高了粉体的松装密度和流动性,还显著提升了陶瓷生坯的烧结性能。此外,将硅溶胶和氧化铝亚微米陶瓷粉体配制成浸渗溶液,依次对铝基陶瓷素坯和脱脂后陶瓷生坯浸渗,可大幅提升其力学性能。SLS成形铝基铸形烧结后x/y轴方向收缩率仅为1.5%,z轴收缩率约为2.0%,室温和1550℃高温抗弯强度达(29.84±6.06)MPa和(18.10±1.25)MPa,蠕变为0.01%。结论利用该铝基陶瓷铸型成功铸造出单晶/柱晶涡轮叶片。结果表明,经原料和工艺优化,可实现高性能复杂结构陶瓷铸型的一体化制备。The work aims to develop a new forming technology to integrally fabricate complex-shaped alumina-based ce-ramic mold,so as to solve the problems of long processing cycle and difficult processing of complex structures of alumi-num-based ceramic molds prepared by traditional forming methods.The selective laser sintering(SLS)additive manufacturing technology was adopted to integrate the formation of a alumina-based ceramic core containing a shell,that is,the integrated core/shell mold.By grading spherical Al2O3 powder particles with different particle sizes and adding a small amount of gas-phase SiO2 flow aid,the loose density and flowability of the composite powders were improved and the sintering perform-ance of alumina-based ceramic green-bodies was significantly enhanced.In addition,a infiltration solution was prepared by mixing silica sol and Al2O3 submicron ceramic powders.The SLS formed alumina-based ceramic green-body and the alu-mina-based ceramic brown-body after debinding were sequentially infiltrated into the above solution,which greatly improved the mechanical properties.For the SLS formed sintered alumina-based ceramic mold,the line shrinkage at x/y axis direction was only 1.5%,along with a shrinkage of about 2.0%at the z axis direction,the room-temperature bending strength reached(29.84±6.06)MPa,the high-temperature bending strength at 1550 reached℃(18.10±1.25)MPa and the creep deformation at 1550 was 0.01%.Finally,single crystal/columnar crystal turbine blades are successfully cast by the SLS formed al℃u-mina-based casting.The results indicate that the high-performance and complex-shaped alumina-based ceramic mold can be fabricated through the synergistic optimization of raw materials and processes.

关 键 词：燃气轮机 叶片 铸造 铝基陶瓷铸型 选区激光烧结 

分 类 号：V231.43[航空宇航科学与技术—航空宇航推进理论与工程]