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研究了采用添加成孔剂法制备具有相互贯通气孔的多孔生物玻璃陶瓷的方法及其性能.多孔玻璃陶瓷主晶相为氟磷灰石和β-硅灰石,气孔率在49％-82％间连续可控,气孔由成孔剂热解排除形成的球形宏观孔(孔径200-850μm)和玻璃粉体烧结形成的微观孔(孔径2-4μm)组成,宏观孔孔径取决于成孔剂粒径并通过孔壁上的孔洞(孔径50-300μm)相互连通.塑性成孔剂硬脂酸受压产生塑性变形,添加硬脂酸的素坯强度高、可加工,烧结产物强度较高、气孔为扁球状;刚性成孔剂聚苯乙烯受压产生弹性变形,添加聚苯乙烯的素坯疏松、不可加工,烧结产物强度较低、气孔呈圆球状.成形压力对添加塑性成孔剂的样品性能影响显著,而对添加刚性成孔剂的样品性能无显著影响.气孔率与成孔剂的含量成良好的线性关系,通过控制成孔剂粒径和加入量可达到气孔率、孔径可控的目的.孔径一定时抗压强度与总气孔率成良好的二次曲线关系.

This study presents the manufacture of highly porous biological glass-ceramic with interconnected pores by adding porosifier, and its main
crystallized products are fluroapatite and wollastonite. The effects of preparation conditions involving porosifier deformation during pressing
(die-pressing technique), particle size and content, and forming pressure on the resultant porosity, pore size as well as structure and mechanical
properties were investigated. The experimental results demonstrate that the resultant porous glass-ceramic with a successful control of pore size
and 50%～82% volume fraction porosity can be obtained. Macropores with 250～850μm diameter forming through the pyrolysis of porosifier
interconnect through the holes with 50～300μm diameter in pore wall. Very little pore volume results from micropores with 2～4μm diameter
because of the incomplete sintering of glass particles. Due to plastic deformation under pressure, the green body that is added plastic porosifier
stearic acid is with high-strength and can be machined into complex shape, and the sintered products with flat-sphere shape macropores are with
high-strength also. On the contrast, because of elastic deformation of rigid porosifier polystyrene under pressure, green body is with low-strength
and can’t be machined, and the sintered products with round-sphere shape macropores are with low-strength also. The forming pressure has a strong impact on the properties of samples with plastic porosifier stearic acid,
but do not influence the properties of samples with rigid porosifier polystyrene significantly. The total porosity correlates with the weight content of
porosifier linearly, so the porosity and pore diameter can be controlled through controlling the porosifier size and its content. The compressive
strength increases with increased porosi