**10. Conclusion**

This chapter focused on finding material properties for two models defined as core-filled model, Type 1, and core-spaced model, Type 2, created by the 3D printing direct metal laser sintering (DMLS) technique. The models use aluminum alloy AlSi10Mg powder with a skill of direct laser sintering. After the uniaxial compressive test, it is proved that core-filled model has an elastic modulus of 19.7%, compressive yield strength of 12.2%, ultimate strength of 294.8%, and percentage of elongation of 11% higher than core-spaced model. It also shows core-filled model have a higher strength but core-spaced model shows a lower strength after compression. There shows two issues that melted metals by DMLS skill are not connected with each other like a solid precisely and there shows a space in additive layer when additive manufacturing makes a shape of specimen. These issues are the main reasons for weaker strength or lower elastic modulus in the models. It is hoped that the two models be made sandwich core structure and then the structure be investigated more deeply. In nearby future, it is hope that 3D printing techniques such as FDM [8, 10], SLS [9], DLP [7, 8], SLA [11, 13], LOM [11, 14], SL [14], MPSL [14], 3DP [14], FFF [15, 16], or DMLS [17, 18] are applied into making hypercube models and then it is to do the testing to check what is the differences of mechanical properties are. In addition, it is expected that hypercube models are applied into make a sandwich panel and then they are to be obtained to find mechanical properties. Finally, it is hope that the sandwich panels will be approved to be selected as one of aerospace materials.

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**Author details**

Chang-won, Republic of Korea

\*Address all correspondence to: choicaf@gmail.com

provided the original work is properly cited.

Jeongho Choi

*Research of Lightweight Structures for Sandwich Core Model*

This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education

School of Mechanical Engineering, College of Engineering, Kyungnam University,

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

*DOI: http://dx.doi.org/10.5772/intechopen.86852*

(grant number NRF-2018R1D1A1B07041383).

I confirm there are no conflicts of interest.

Many thanks go to Dr. Sang-ik Lee for doing this project.

**Notes/thanks/other declarations**

**Acknowledgements**

**Conflict of interest**
