Revealing plastic strain in hot deformed TiB/Ti composites using fiber-orientation based analysis

The state of plastic strain can heavily influence the microstructure and mechanical properties of metallic products produced by plastic forming. However, low-cost, ex-situ methods are lacking to quantitatively identify the plastic strain inside bulk materials. As a result, the accuracy of the processing parameters – microstructure – properties relationship is limited. Utilizing the rigid rotation behavior of ceramic reinforcements in TiB/Ti composites, a fiber orientation-based analysis (FOBA) is proposed to reveal the state of plastic strain. To this end, the quantitative relationship between the plastic strain tensor and the distribution of fiber orientations was first deduced, error analysis was then carried out, and the state of plastic strain in a hot-rolled TiB/Ti composite plate was calculated to demonstrate the experimental procedure. To demonstrate the potential application of FOBA, the complex strain distribution in a hot-compressed TiB/Ti sample was reconstructed and compared with the distortion of TiB network structure. The results showed that FOBA has good accuracy when calculating the strain in samples with height reductions ranging from 20% to 80%. This work presents an accurate, cost-effective, and feasible method to assess the plastic strain in short-fiber-containing bulk materials.