Microstructure and properties of inter/inner-layer regions of TiCp/Ti6Al4V composites manufactured by laser melting deposition

• Published in: Materials letters 2022-06, Vol.316, p.131989, Article 131989
• Main Authors: Zeng, Yuzhou, Wang, Jiandong, Wei, Junzhe, Xue, Yu, Zhao, Ziang, Tang, Lang, Li, Liqun, Tong, Yunxiang, Jiang, Fengchun
• Format: Article
• Language: English
• Subjects: Additive manufacturing; Composite materials; Deposition; Distribution; Interlayers; Laser beam melting; Materials science; Metallic composites; Microstructure; Tensile properties; TiC particles; Titanium base alloys; Titanium carbide
• ISSN: 0167-577X; 1873-4979
• DOI: 10.1016/j.matlet.2022.131989

•Undissolved TiC is found to gather at interlayer regions in TiCp/Ti6Al4V composites.•Mechanisms of non-uniform distribution of undissolved TiC particles are expounded.•Inner-layer regions have better tensile properties than interlayer regions. 5 vol% TiCp/Ti6Al4V and 20 vol% TiCp/Ti6Al4V composites are manufactured by laser melting deposition. Non-uniform gathering phenomenon of undissolved TiC has been found in the interlayer regions of deposits, which is resulted from temperature gradient and Marangoni flow in the molten pool. Inner-layer regions have better tensile properties than interlayer regions due to lower local content of undissolved TiC. Undissolved TiC particles adversely impact the ductility and strength of composites because of their brittleness per-se, their larger sizes and the flaws in them.