Hydroxyapatite scaffold is a type of bio-ceramic. Its cellular design has similarities with the morphologies in nature. Therefore, it is very important to control the structure, especially the porosity, as one of the main features for bio-ceramics applications. According to some literature, freeze casting can form the shape of dendrites and remain a foam structure after ice sublimation. Ice nucleation became more heterogeneous with the aid of printing materials during freeze casting. This procedure can even improve the issue of crack formation. In this paper, we studied the mechanical properties of hydroxyapatite scaffold. We also analyzed the porosity by fractal nature characterization, and successfully reconstructed pore shape, which is important for predicting ceramic morphology. We applied SEM analysis on bio-ceramic samples, at four different magnifications for the same pore structure. This is important for fractal analysis and pores reconstruction. We calculated the fractal dimensions based on measurements. In this way, we completed the fractal characterization of porosity and confirmed possibilities for successful porous shapes reconstruction. In this paper, we confirmed, for the first time, that fractal nature can be successfully applied in the area of porous bio-ceramics.

中文翻译：

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多孔结构生物陶瓷的分形性质分析

羟基磷灰石支架是一种生物陶瓷。它的细胞设计与自然界的形态有相似之处。因此，控制结构，特别是孔隙率，作为生物陶瓷应用的主要特征之一是非常重要的。根据一些文献，冷冻铸造可以形成枝晶的形状并在冰升华后保持泡沫结构。在冷冻铸造过程中，借助打印材料，冰核变得更加不均匀。这个程序甚至可以改善裂纹形成的问题。在本文中，我们研究了羟基磷灰石支架的力学性能。我们还通过分形性质表征分析了孔隙率，并成功地重建了孔隙形状，这对于预测陶瓷形态很重要。我们对生物陶瓷样品进行了 SEM 分析，对于相同的孔结构，在四个不同的放大倍数下。这对于分形分析和孔隙重建很重要。我们根据测量值计算了分形维数。通过这种方式，我们完成了孔隙度的分形表征，并确认了成功重建孔隙形状的可能性。在本文中，我们首次证实了分形性质可以成功地应用于多孔生物陶瓷领域。