颗粒造孔制备多孔钛中结构及性能影响因素

Effects of Processing Condition on Microstructure and Properties of Porous Titanium Prepared by Porogen-based Vacuum Sintering

选用粒径为10-40μm的钛粉和粒径为100-375μm的碳酸氢铵，使用占位填料法制备多孔钛，在10^-3Pa真空压力下进行烧结。研究了烧结温度、保温时间及升温速率对多孔钛微结构及力学性能的影响。结果表明：烧结温度1200℃、保温时间2h、升温速率4．2min／℃的条件下，多孔钛性能最佳，其孔隙率为63．5％，开孔率为64．9％，抗压强度为150．7MPa，弹性模量为2．91GPa；烧结温度和保温时间对性能影响较大而升温速率影响较小；多孔钛的抗压强度、弹性模量和人骨的抗压强度及弹性模量较为接近，可作为人骨的替代材料。

The porous Ti was prepared by vacuum sintering （10^-3 Pa） of Ti powders （10-40 μm） using ammonium bicarbonate （100-375 μm） as the porogen. The effects of heating rate, sintering temperature and sintering time on the porous Ti were systematically investigated. The results show that , sintering temperature and time has significant effects on the microstructure and mechanical properties of the porous Ti, while the effects of heating rate are limited. The optimum processing conditions are： heating rate 4.2 min/℃ and sintering at 1200 ℃ for 2 h. The porous Ti prepared under these optimum conditions has a total porosity of 63.5%, open porosity of 64.9%, compressive strength of 150.7 MPa and Young＇s modulus of 2.91 GPa. These properties are similar to those of human trabecular bone, which can suggest that the porous Ti prepared in this study can be used as bone substituting material.