Prof. Haihong Zhu and Dr. Jie Yin's collaborative paper "High-power laser-matter interaction in selective laser melting" won the Best Paper Award (Top ~2%) at the First International Academic Conference on the Research Advances in Additive Manufacture (RAAM), Prof. Xiaoyan Zeng participates in the guidance. This paper was recommended for publication on international academic journal Additive Manufacturing (Impact Factor 2018: 7.173).
Fig. 1 The First International Academic Conference on the Research Advances in Additive Manufacture (RAAM)
Ø Background and our research work
Selective laser melting (SLM) additive manufacturing (AM) is developing with the goal of fabricating parts with high performance and high efficiency. Laser power not only determines the fabrication rate and expands the scope of SLM processing in terms of materials, but also directly influences the characteristics of the thermal behavior and molten pool evolution; thus, the laser power consequently determines the microstructure, surface quality and performance of the final part. However, there are limited reports regarding the laser-matter interaction in SLM under high-power conditions, which hinders the understanding of the formation mechanism in high-power SLM.
Fig. 2 Mechanism of the large spatter generation in high-power SLM (paper illustration)
In this work, the occurrence, evolution of the vapor depression and protrusion in the molten pool of SLM under the conditions of high power (>1 kW) and a wide window were studied based on a high-speed high-resolution imaging. Results show that the molten pool characteristics and spatter behavior depend on the laser energy input. The average ejection velocity and ejection angle increase with the laser power. Large spatters are prone to generation under the high-power laser. Furthermore, the occurrence time of physical phenomenon declines dramatically with the increase of the laser energy input.
Fig. 3 High-speed high-resolution imaging of laser-matter interaction in SLM under high-power conditions (paper illustration)
This work provides a deep understanding of the laser-matter interaction under high-power conditions, which is of vital significance to the physical basis of the high-power SLM process and the properties of a part that is processed by SLM. Therefore, this work will be of great interest to physicists and engineers working in additive manufacturing.
Ø Authors and acknowledgement
Dr. Jie Yin is the first author of this paper, Prof. Haihong Zhu is the correspondent author, Prof. Xiaoyan Zeng participates in the guidance. The co-authors are Prof. Guoqing Wang from China Academy of Launch Vehicle Technology, Dr. Linda Ke from Shanghai Spaceflight Precision Machinery Institute and master students Liangliang Yang and Xu Yang in WNLO.
Fig. 4 Dr. Jie Yin won the Best Paper Award and delivered a speech
This work was supported by the National Natural Science Foundation of China (61805095 and 61475056), National Program on Key Basic Research Project of China (613281), Shanghai Aerospace Science and Technology Innovation Fund (SAST2017-58) and China Postdoctoral Science Foundation funded project (2018M642832).
Fig. 5 Prof. Jean-Pierre Kruth, University of Leuven, presented the award to the winners
Ø About RAAM
It is reported that the First International Academic Conference on the Research Advances in Additive Manufacture (RAAM) was held in Nanjing from March 3rd to 5th, 2019. Prof. Dave Bourell from the University of Texas at Austin, and Prof. Wenhe Liao from Nanjing University of Science and Technology are the chairs the conference. The conference focused on the latest scientific research achievements, innovations and applications in additive manufacturing. It was the extension of International Solid Freeform Fabrication Symposium (SFF) in Asia and showed the vigorous development of additive manufacturing technology in Asia.
