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The purpose of this paper consists in the optimization and understanding of the Selective Laser Melting (SLM) manufacturing process of biomaterials, such as T40 and CoCrMo, as scaffolds. Moreover, process optimization is also challenging, with regards to the huge number of parameters and their influence on the finished product.

The paper opted for an exploratory study using Taguchi analysis method to precisely identify the most relevant parameters and justify the energy estimation.

The study showed that SLM fits perfectly with the T40 and CoCrMo part manufacturing. This method allowed to have a complete overview of all the potential applications of SLM for implant manufacturing.

With this research approach, the results may be generalized to other material and showed a good theoretical approach.

The purpose of this paper is to investigate the effect of remelting each layer on the homogeneity of nickel-titanium (NiTi) parts fabricated from elemental nickel and titanium powders using laser powder bed fusion (LPBF). In addition, the influence of manufacturing parameters and different melting strategies, including multiple cycles of remelting, on printability and macro defects, such as pore and crack formation, have been investigated.

An LPBF process was used to manufacture NiTi alloy from elementally blended powders and was evaluated with the use of a remelting scanning strategy to improve the homogeneity of fabricated specimens. Furthermore, both single melt and up to two remeltings were used.

The results indicate that remelting can be beneficial for density improvement as well as chemical and phase composition homogenization. Backscattered electron mode in scanning electron microscope showed a reduction in the presence of unmixed Ni and Ti elemental powders in response to increasing the number of remelts. The microhardness values of NiTi parts for the different numbers of melts studied were similar and ranged from 487 to 495 HV. Nevertheless, it was observed that measurement error decreases as the number of remelts increases, suggesting an increase in chemical and phase composition homogeneity. However, X-ray diffraction analysis revealed the presence of multiple phases regardless of the number of melt runs.

For the first time, to the best of the authors’ knowledge, elementally blended NiTi powders were fabricated via LPBF using remelting scanning strategies.