Analysis of abnormal bright band characteristics of forging for a new low-cost titanium alloy

•A centimeter-scale defective microstructure is named as the ABBC.•The reason for the formation of the ABBC has been clarified.•Reconstructed β phase in the ABBC is a standard cube texture.•The formation of the ABBC is caused by the AGG of cube-grain. A centimeter-scale defective microstructure, namely abnormal bright band characteristics (ABBC), is found in engineering production of titanium alloy forgings, and it seriously affects the stability and reliability of performance. The targeted work for the reason of the formation of the ABBC is carried out in this paper. The ABBC contains a large number of small colony α, without grain boundary. The α phase in the ABBC includes 12 variants from one β grain. The crystallographic orientation of reconstructed β phase in the ABBC is a standard cube texture. The formation of the ABBC is caused by the abnormal grain growth (AGG) of cube-grain. The cube-grain is a low energy storage grain, which can merge with other grains to grow rapidly.