Theoretical Analysis of Self-Shrinkage Spheroidization of Irregular Degradable Polymer Powder under Thermodynamic Nonequilibrium State  

作　　者：Xiong Shuai liuyimei Yang Fangwei Qi Mingli Yang Youwen Yang Cijun Shuai 

机构地区：[1]Institute of Additive Manufacturing,Jiangxi University of Science and Technology,Nanchang,330013,China [2]Ganjiang Innovation Academy,Chinese Academy of Sciences,Ganzhou,341119,China [3]School of Mechanical and Electrical Engineering,Jiangxi University of Science and Technology,Ganzhou,341000,China [4]State Key Laboratory of Precision Manufacturing for Extreme Service Performance,College of Mechanical and Electrical Engineering,Central South University,Changsha,410083,China [5]School of Sino-German Robotics,Shenzhen Institute of Information Technology,Shenzhen,518172,China

出　　处：《Additive Manufacturing Frontiers》2024年第4期232-241,共10页增材制造前沿(英文)

基　　金：supported by National Key Research and Development Program of China(Grant No.2023YFB4605800);Natural Science Foundation of China(Grant Nos.51935014,52365046,52105352,82072084);JiangXi Provincial Natural Science Foundation of China(Grant No.20224ACB204013);Schig-Qinling Program(Grant No.2022360702014891).

摘　　要：Laser three-dimensional(3D)printing offers significant advantages in integrating the shape and function of regen-erative tissues through biomimetic manufacturing.However,its effectiveness is limited by the lack of specialized biopolymer powders-while solvent methods that use residual solvents produce powders with poor biocompati-bility,mechanical methods result in irregularly shaped crystals.In this study,a biopolymer powder spheroidiza-tion and shaping technology,which utilizes the evolution of irregular powders into spheres with minimal surface free energy in the molten state,is proposed based on the thermodynamic principle of minimum energy.Initially,the motion trajectory and temperature field of the poly(L-lactic acid)(PLLA)powder during spheroidization were quantitatively assessed and optimized using Stokes’law and Fourier’s principle.Subsequently,the cohesive forces and aggregation kinetics of the polymer chains were calculated using molecular dynamics.Finally,based on these calculations,a phase-field model was constructed to simulate the evolution of the spheroidization rate and deduce the optimal parameters for the process.This precise approach enhances PLLA spheroidization control for laser 3D printing,improves part densification and surface quality,and offers a clean and efficient path for preparing high-quality PLLA spheroidized powder for laser 3D printing.

关 键 词：Polymer powder SPHEROIDIZATION PLLA Selective laser sintering 3D printing 

分 类 号：TB3[一般工业技术—材料科学与工程]