A new processing route is proposed to produce graded porous materials by placing particles of Ti6Al4V with different sizes in different configurations to obtain bilayer samples that can be used as bone implants. The sintering behavior is studied by dilatometry and the effect of the layers’ configuration is established. To determine pore features, SEM and computed microtomography were used. Permeability is evaluated by numerical simulations in the 3D real microstructures and the mechanical properties are evaluated by compression tests. The results show that a graded porosity is obtained as a function of the size of the particle used. The mechanical anisotropy due to the pore size distribution and the sintering kinetics, can be changed by the particle layer arrangements. The Young modulus and yield stress depend on the relative density of the samples and can be roughly predicted by a power law, considering the layers’ configuration on the compression behavior. Permeability is intimately related to the median pore size that leads to anisotropy due to the layers’ configuration with smaller and coarser particles. It is concluded that the proposed processing route can produce materials with specific and graded characteristics, with the radial configuration being the most promising for biomedical applications.

中文翻译：

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骨科应用固态烧结双层材料的加工与表征

提出了一种新的加工路线，通过将具有不同尺寸的Ti6Al4V颗粒放置在不同的结构中，以获得可以用作骨植入物的双层样品，从而生产渐变的多孔材料。通过热膨胀法研究了烧结行为，并确定了层结构的影响。为了确定孔特征，使用了SEM和计算机断层摄影术。通过在3D实际微观结构中的数值模拟来评估渗透率，并通过压缩测试来评估机械性能。结果表明，获得的孔隙率是所用颗粒尺寸的函数。由于孔径分布和烧结动力学而引起的机械各向异性可以通过颗粒层的布置来改变。杨氏模量和屈服应力取决于样品的相对密度，并且可以通过幂定律粗略地预测，考虑层在压缩行为上的构型。渗透率与中值孔径密切相关，中值孔径会导致各向异性，这是由于层的颗粒较小和较粗而导致的。结论是，提出的加工路线可以生产具有特定和分级特性的材料，其中径向构型是生物医学应用中最有希望的材料。