Steel parts manufactured with laser-based powder bed fusion of metals (PBF-LB/M) technology usually have high strength and ductility due to their ultra-fine heterogeneous microstructure. However, defects or oxide inclusions are inevitably formed during the forming process, leading to stress concentration and severely reducing the formed parts’ toughness, resulting in part fracture.
In response to the above problems, the research team led by Professor Chen Hao of Tsinghua University proposed a toughening strategy based on chemically heterogeneous metastable austenite, aiming to explore the potential of chemically heterogeneous austenite design in improving the impact toughness of high-strength steel. Research has shown that the toughness of martensitic steels can be adjusted by introducing an appropriate proportion of chemically heterogeneous austenite into the martensite matrix. The austenite in high-strength steel not only absorbs energy through the transformation-induced plasticity (TRIP) effect produced by deformation-induced martensitic transformation (DIMT), but also promotes local stress release, passivating and deflecting cracks, thus significantly affecting the ductility and toughness of steel. The research “On the role of chemically heterogeneous austenite in cryogenic toughness of maraging steels manufactured via laser powder bed fusion” was published in the international academic journal Acta Materialia.
BLT provided machine support for this research. The researchers used BLT-S210 to prepare samples and successfully prepared maraging stainless steel samples with significantly improved toughness, which verified the research hypothesis and provided a new strategy for the design of high-strength steel with excellent low-temperature toughness. .
BLT is deeply engaged in scientific research and is committed to providing machine & system, technical consulting, cooperative development, and other products and services to clients in this field, with over 330 clients by the end of 2023. Since 2024, BLT has supported Tsinghua University, Peking University, Shanghai Jiaotong University, Beihang University, Northwestern Polytechnical University, Chinese Academy of Sciences, and other universities and scientific research institutions in the fields of aerospace and medical, among others, making numerous breakthroughs in the research of new materials, new structures, and new applications.
