Microstructure and inclusion of Ti–6Al–4V fabricated by selective laser melting

Abstract

Selective laser melting (SLM) was used in fabricating the dense part from pre-alloyed Ti–6Al–4V powder. The microstructural evolution and inclusion formation of as-fabricated part were characterized in depth. The microstructure was characterized by features of columnar prior β grains and acicular martensite α'. High density defects such as dislocations and twins can be produced in SLM process. Investigations on the inclusions find out that hard alpha inclusion, amorphous CaO and microcrystalline Al₂O₃ are three main inclusions formed in SLM. The inclusions formed at some specific sites on melt pool surface. The microstructural evolution and inclusion formation of as-fabricated material are closely related to the SLM process.

Keywords

metals and alloys / laser processing / microstructure / inclusion

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Acknowledgements

The authors are grateful for the financial support from the National Natural Science Foundation of China (Grant No. 81260281).

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2016 Higher Education Press and Springer-Verlag Berlin Heidelberg