Additive manufacturing of Ti-Al functionally graded material by laser based directed energy deposition

• Published in: Rapid prototyping journal Vol. 29; no. 3; pp. 558 - 568
• Main Authors: Chen, Bo, Wang, Tao, Xi, Xin, Tan, Caiwang, Song, Xiaoguo
• Format: Journal Article
• Language: English
• Published: Bradford Emerald Group Publishing Limited 02.03.2023
• Subjects: Additive manufacturing; Aerospace industry; Aluminum; Composite materials; Composite structures; Cooling; Cracks; Deposition; Diamond pyramid hardness; Functionally gradient materials; High temperature; Interfacial stresses; Interlayers; Intermetallic compounds; Laser applications; Lasers; Manufacturing; Mechanical properties; Melting; Microstructure; Phase distribution; Rapid prototyping; Residual stress; Solidification; Stress concentration; Titanium alloys; Titanium aluminides
• ISSN: 1355-2546; 1355-2546; 1758-7670
• DOI: 10.1108/RPJ-04-2022-0117

PurposeTi-Al composite plates have been used in aerospace and other important fields for specific purposes in recent years. However, relatively few studies have concentrated on Ti-Al additive manufacturing because during additive manufacturing process the local fusion and mixing of Ti/Al are inevitable. These areas where Ti and Al are mixed locally, especially interface, could easily generate high residual stresses and cracks. This study aims to manufacture Ti-Al functionally graded material and investigate the interaction of interface.Design/methodology/approachIn this study, Ti6Al4V/AlSi10Mg functionally graded materials were fabricated by laser based directed energy deposition (L-DED) and a strategy using V interlayer to relieve interfacial stress was investigated.FindingsThe area between the two materials was divided into transition zone (TZ) and remelting zone (RZ). The phase distribution, microstructure and micro-Vickers hardness of the TZ and RZ were investigated. Typical intermetallic compounds (IMCs) such as TiAl3, Ti3Al and Ti5Si3 were found in both composites. The addition of V interlayer promoted the homogenization of IMCs near interface and led to the formation of new phases like V5Si3 and Al3V.Originality/valueThe solidification process near the interface of Ti-Al functionally graded material and the possible generation of different phases were described. The result of this paper proved the feasibility of manufacturing Ti-Al functionally graded material by L-DED.