Research progress of laser powder bed fusion of Ti2AlNb-based alloys: Microstructure, defects and properties
Jianfa Liao, Aoqi Fan, Haojie Luo, Yulei Du
Abstract
Ti 2 AlNb-based intermetallic alloys have emerged as promising candidates for aeroengine components due to their exceptional strength-to-weight ratio and superior high-temperature performance. Laser powder bed fusion (LPBF) has garnered considerable attention in the development of Ti 2 AlNb-based alloys because it enables the fabrication of complex structural parts with intricate geometries. However, LPBF-fabricated Ti 2 AlNb alloys still encounter significant challenges, including difficulties in microstructure control, the presence of various defects, and inadequate high-temperature ductility, which severely restrict their practical applications. This paper offers a comprehensive review of recent advancements in LPBF-built Ti 2 AlNb alloys and explores the interrelationships among microstructure, defects, and properties. First, we summarize the fundamental structure and properties of Ti 2 AlNb-based alloys. Next, we provide an in-depth examination of LPBF process characteristics and powder preparation methods. Subsequently, we describe the unique microstructural features of LPBF-built Ti 2 AlNb alloys and discuss the formation mechanisms of defects such as porosity and cracking, along with corresponding mitigation strategies . We also summarize effective methods for enhancing mechanical properties. Finally, we propose future development directions, including the design of new alloy compositions , crack control, optimization of heat treatment processes , and performance evaluation of practical engineering components.