Pioneering the forefront of scientific innovation in an era reshaped by cutting-edge technology, the search for materials that harmoniously blend lightness with strength continues. This journey is not just about inventing new materials; it’s about expanding the limits of what’s achievable in sectors such as aerospace and automotive engineering. The magic lies in the microstructure of materials – those tiny, often invisible patterns that determine a material’s characteristics. Deciphering and manipulating these patterns can lead to significant breakthroughs, paving the way for advancements that were once thought impossible.

Researchers from the Xi’an University of Technology in China, led by Professor Shufeng Li, have made significant strides in the realm of aerospace and automotive materials through their work on nano-scale titanium boride whiskers (TiBw) reinforced titanium matrix composites (TMCs).

Their research, centered on the influence of the scale characteristic parameters (such as the diameter, aspect ratio, and dispersion) of TiBw on the microstructure and mechanical behavior of TMCs, offers crucial insights into the relationship between microstructure and mechanical properties. “The material microstructure determines its macroscopic properties. we are committed to actively regulating the microstructure of TMCs” Professor Li noted, highlighting the importance that dictates the material’s behavior at a microscopic level.

To prepare the composites, the team proposed to design a spherical Ti64-TiBw composite powder, containing nano-scale TiBw via a process known as electronic induction melting gas atomization (EIGA), and further prepare Ti64-TiBw composites through EBM method, to control the scale characteristic parameters of TiBw in TMCs effectively. “In the spherical Ti64-TiBw composite powders we designed, TiBw is distributed along grain boundaries at the nano-scale, forming a discontinuous network structure. And this network structure is maintained in the EBM-Ti64-TiBw composites.” explained Dr. Liu, illuminating the complex architecture of these materials.

These TMCs, renowned for their exceptional strength, stiffness, and high-temperature resistance, are pivotal in high-tech industries, particularly aerospace and automotive. Professor Shufeng Li shed light on the importance of their findings, “By utilizing the rapid cooling process in EIGA and EBM, nano-scale TiBw can be obtained in TMCs. This provides an experimental basis for researchers to broaden the TiBw size control window and study the effect of TiBw size on the microstructure and properties of TMCs.”

The study underscores the importance of understanding the evolution of the scale characteristic parameters TiBw in TMCs. ” With increasing heat treatment temperature, the nano-scale TiBw begin to coarsen to micro-scale in EBM-Ti64-TiBw composites, leading to a changing of the microstructure on Ti64 matrix. The enlargement of TiBw follows a natural growth mechanism known as Ostwald ripening,” Professor Li noted.

This groundbreaking work opens avenues for developing advanced materials vital for the aerospace and automotive industries. The capability to fine-tune these composites’ properties offers opportunities for producing materials that are both lightweight and robust, meeting the high standards of these sectors.

Journal Reference

Yiming Zhang, Shufeng Li, Shaodi Wang, Deng Pan, Lei Liu, Shaolong Li, Lina Gao, Huiying Liu, Xin Zhang, Bo Li, Shengyin Zhou. “Microstructure evolution of Ti64-TiBw composites via electron beam powder bed fusion using as-prepared composite powder as feedstock.” Journal of Materials Research and Technology 27 (2023). DOI: https://doi.org/10.1016/j.jmrt.2023.11.159.

About the Authors

Lei Liu was born in Xi’an, China, in 1994. He is a PhD candidate. He received the B.S. degree in Material Physics, M.S. degrees in Material Science and Engineering from Xi’an University of Technology, Xi’an, China, in 2017 and 2020, respectively. From 2023 to 2024, he was an International Joint Research Collaborator in Joining and Welding Research Institute, Osaka University, Osaka, Japan. His research focuses on the deformation mechanisms and mechanical behaviors of heterostructured titanium matrix composites by powder metallurgy and additive manufacturing.

Shufeng Li, PhD, is a Professor of the School of Material Science and Engineering at Xi’an University of Technology, and an Invited Professor of the Joining and Welding Research Institute at Osaka University. He is also the director of the Shannxi Key Laboratory of Powder Metallurgy and Additive Manufacturing Metal Matrix Composite and the Xi’an Key Laboratory of Advanced Powder Metallurgy Materials and New Technology. Dr. Shufeng Li received his Bachelor’s degree and Master’s degree in Material Shaping and Controlling at Xi’an University of Technology, Xi’an, China, and his PhD degree in Mechanical Engineering at Nihon University, Tokyo, Japan. From 2009 to 2012, he performed postdoctoral research at the Joining and Welding Research Institute at Osaka University. From 2012 to 2013, he was a Special Appointed Assistant Professor at the Osaka University, Osaka. He received the Research Progress Award of the Japan Powder Metallurgy Association in 2013, and the Science and Technology Award from the Minister of Education, Culture and Science of Japan in 2014. Dr. Shufeng Li’s research focuses on studying the regulation of cardiac ion channels and arrhythmogenic mechanisms. He has published close to 200 peer-reviewed original research papers in well-known international journals such as PNAS, Acta Materialia and Additional Manufacturing.