TiB nano-whiskers reinforced titanium matrix composites with novel nano-reticulated microstructure and high performance via composite powder by selective laser melting

摘要

TiB nano-whiskers reinforced titanium matrix composites (Ti-TiBw) with a unique nano-reticulated micro-structure was prepared via composite powder by selective laser melting (SLM). The composite powder was designed and produced by electrode induction melting gas atomization as starting materials for SLM other than the conventional premixed Ti-TiB_2 powders. The new composite powder had a micron-scale reticulated structure with micro-nano TiBw along the grain boundaries, which was further refined to nano-scale during SLM attributing to the rapid solidification rate. The SLMed Ti-TiBw composites exhibited exceptional strength (σ_b = 851 MPa) while maintaining good ductility (δ = 10.2%), which was tightly related to our novel strategy of micro-structural configuration.