基于拓扑优化和参数自适应的PA12/n-HA非线性梯度多孔结构SLS成形性能调控

研制充分结合羟基磷灰石(HA)生物活性与高分子材料力学性能的多孔支架，从而用于骨修复成为当今生物医疗研究中的热点。但传统的多孔制备方法难以控制孔隙率及尺寸，不能满足活性支架非线性功能梯度、复杂结构的个性化要求。本课题拟基于选区激光烧结技术(SLS)，围绕尼龙12(PA12)和纳米HA(n-HA)复合材料多孔结构设计与梯度功能调控展开基础研究。主要内容包括：多组分材料选区激光烧结有限元数值模型与多尺度分析；SLS工艺优化与加工质量主动控制；参数驱动的多孔结构非线性梯度调控策略。本项目旨在揭示PA12/n-HA复合材料的激光烧结成形机制，建立孔隙结构、工艺参数与力学性能间的定量表征关系，提出拓扑结构优化模型与工艺参数自适应控制策略，形成具有非线性功能梯度特征的多孔结构SLS成形工艺规范。本项目的研究成果可为复合材料构件的SLS工艺提供理论指导和技术支持，为组织工程支架的设计和制造提供技术保障。

Porous scaffold for bone repair, which combines the bioactivity of hydroxyapatite (HA) of the mechanical property of polymer materials, has been a focus in biomedical research. However, conventional manufacturing methods cannot control the porosity and pore size, and doesn’t meet the personalized requirements of nonlinear functionally graded structures of biomedical scaffold. Thus, in this work, based on selective laser sintering (SLS), the porous structure design and its gradient function control strategy of PA12/n-HA composites are researched. The main contents are as follows. (1) Finite element model and multi-scale analysis of SLS of multicomponent materials. (2) Process optimization and active control of sintering quality. (3) Parameters driven porous structure design and nonlinear gradient function regulation. The project aims to reveal the laser sintering mechanism of PA12/n-HA composite, to quantitatively analyze the correlation between porosity, process parameters and sintering performance, to set up the porous topology optimization model and self-adaption control strategy of manufacturing parameters, and finally to constitute the technological design of SLS process of nonlinear graded porous structures with a high degree of consensus. The research results of this project would provide a theoretical guidance and technical assistance for SLS process of composite structures, and also provide a technical support for the design and manufacturing of tissue scaffold.