多孔钛合金拓扑优化设计及性能研究

Topology Optimization Design and Performance Study of Porous Titanium Alloy

摘要:

为了得到良好力学性能和高渗透性的钛合金多孔结构，需要在多孔结构的孔隙率与其强度之间保持权衡。以人体膝关节胫骨假体为研究对象，首先，根据胫骨受力状态，采用拓扑优化设计并重构不同载荷工况下的抗压、抗剪单胞结构(TO-P1、TO-P2、TO-S1、TO-S2)，与几种常见的基本单胞结构(BCC、FCC、RDC、DCC)进行研究比较；其次，通过对不同类型多孔钛合金进行压缩、剪切性能仿真，研究不同拓扑形态的多孔钛合金关于抗压、抗剪的力学性能，并采用SLM技术成型多孔钛合金压缩试件，验证了仿真分析的有效性；最后，选择力学性能较优的4种多孔钛合金进行渗透性分析。结果表明，TO-S2结构的抗压、抗剪力学性能和渗透性能最为出色，适合作为压剪载荷类植入物的多孔结构。

Abstract:

To obtain titanium alloy porous structures with good mechanical properties and high permeability, a trade-off between the porosity of the porous structure and its strength needs to be maintained. Taking human knee tibial prosthesis as the research object, firstly, according to the stress state of the tibia, topology optimization is used to design and reconstruct the compressive and shear cell structures (TO-P1, TO-P2, TO-S1, TO-S2) under different loading conditions, and several common basic cell structures (BCC, FCC, RDC, DCC) are studied and compared; secondly, by performing different types of porous titanium alloys for compression and shear performance simulation, to research the mechanical properties of porous titanium alloys with different topologies regarding compression and shear resistance, and to verify the validity of the simulation analysis by forming porous titanium alloy compression specimens with SLM technology; finally, four porous titanium alloys with better mechanical properties were chosen for permeability analysis. The results show that the TO-S2 structure has the best compressive, shear mechanical properties and permeability, suitable for porous structures of compression-shear load type implants.