In situ tailoring microstructure in laser solid formed titanium alloy for superior fatigue crack growth resistance

• DOI: 10.1016/j.scriptamat.2019.08.028
• Publication Date: 2019-08-31T11:23:39Z
• Authors: Zhuang Zhao; Jing Chen; Hua Tan; Jingang Tang; Xin Lin
• Keywords: Titanium alloy; Paris' law; Damage tolerance

Abstract For damage tolerance (DT) titanium alloy, the fatigue crack growth resistance (FCGR) is a critical properties requirement for engineering applications. However, the Ti-6Al-4V-DT parts fabricated by laser solid forming (LSF) suffer from low FCGR, because of predominant basket-wave microstructure. Here, we have explored a novel LSF fabrication design to produce full colony microstructure, via in-situ controlled growth. The creation of such microstructures leads to superior FCGR, which markedly exceed conventional additive manufactured and mill-annealed samples. The present works provide a significant guidance for LSF-fabricated titanium alloy with high DT properties.