填充密度和轮廓层数对浆料挤出3D打印型壳性能的影响  

Effect of Infill Density and Shell Layer Number on Properties of Casting Shell Mould Prepared by Slurry Extrusion-based 3D Printing

作　　者：刘娇 刘洪军[1] Yatskovskyi Dmytro 李亚敏[1] LIU Jiao;LIU Hongjun;Yatskovskyi Dmytro;LI Yamin(State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室,兰州730050

出　　处：《精密成形工程》2024年第9期181-189,共9页Journal of Netshape Forming Engineering

基　　金：国家自然科学基金(52062029);甘肃省重点研发计划(18YF1GA064)。

摘　　要：目的采用浆料挤出3D打印工艺直接制备具有中空网络结构的铸造型壳,研究填充密度和轮廓层数对型壳性能的影响,以优化型壳制备工艺。方法选择直线填充模式,设置填充密度从60%~100%、轮廓层数从1~3,采用铝矾土浆料制备型壳试样,并测试孔隙率、收缩率、弯曲强度和导热性。结果随着填充密度的增加,孔隙率从49.4%持续降低到36.7%,但是降幅不断缩窄;收缩率逐渐减小并具有明显的各向异性,大部分收缩率在1.5%~2.5%;弯曲强度从6.15 MPa迅速提高到9.48 MPa,但填充密度超过80%后增幅很小;铝合金液浇注实验显示导热性呈现增加的趋势。随着轮廓层数增加,孔隙率和导热性逐渐降低;弯曲强度从9.48 MPa逐渐降低到7.61 MPa;轮廓层数为1和2时收缩率相近,轮廓层数为3时收缩率大大提高,尤其是在打印高度方向。结论填充密度和轮廓层数通过改变型壳的内部网格结构和外壁厚度来影响型壳性能,当填充密度为80%和轮廓层数为1时型壳综合性能最优,浆料挤出3D打印工艺制备的型壳经铝合金试铸,验证效果良好。The work aims to adopt slurry extrusion-based 3D printing process to directly prepare casting shell mould with hollow network structure and study the effect of infill density and shell layer number on the properties of the shell mould to optimize the preparation process.The linear infill pattern was selected and the infill density was set from 60%to 100%,and the shell layer number was set from 1 to 3.The bauxite slurry was used to prepare the test samples of shell mould,and the porosity,shrinkage rate,bending strength,thermal conductivity,and surface roughness were investigated.As the infill density increased,the porosity decreased from 49.4%to 36.7%,but the decline range gradually narrowed down.The shrinkage rate continuously decreased and exhibited significant anisotropy,mostly between 1.5%and 2.5%.The bending strength rapidly increased from 6.15 MPa to 9.48 MPa,but the increase was not significant when the infill density exceeded 80%.The pouring experiment of aluminum alloy melt showed an increasing trend in thermal conductivity of shell mould.As the shell layers number increased,the porosity and thermal conductivity gradually decreased.The bending strength gradually decreased from 9.48 MPa to 7.61 MPa.When the shell layer number was 1 or 2,the shrinkage rate was similar,but when the shell layer number was 3,the shrinkage rate greatly increased,especially in the printing height direction.The infill density and the shell layer number affect the properties of the shell mould by changing the internal grid structure and outer wall thickness of the shell mould.When the infill density is 80%and the shell layer number is 1,the comprehensive properties of the shell mould are optimal.The shell mould prepared by slurry extrusion-based 3D printing process has been verified to have good results through trial casting of aluminum alloy.

关 键 词：浆料挤出3D打印 铸造型壳 填充密度 轮廓层数 型壳性能 

分 类 号：TG249.5[机械工程—精密仪器及机械]