Microstructure and tensile behavior of novel laminated Ti-TiBw/Ti composites by reaction hot pressing

A novel laminated Ti-TiBw/Ti composites composed of Ti layers and TiB whisker reinforced Ti (TiBw/Ti) composite layers were successfully fabricated by reaction hot-pressing. Herein, the TiBw/Ti composite layers were in situ synthesized by reaction in the system of Ti and TiB2 powders during the hot pressing process. The composite layer can effectively refine grains of Ti layer. Moreover, in-situ synthesized TiB whiskers obviously restrain the growth of Ti matrix grains of the TiBw/Ti composite layers. It is worth pointing out that the in situ synthesized TiBw can strengthen the interface between Ti layer and TiBw/Ti layer. The tensile testing results show that the ultimate strength and the ductility of laminated composites can be increased to 617 MPa and 20.5%, respectively, from 546 MPa and 17.5% of pure Ti, indicating that the strengthening effect and the toughening effect of the composites were effectively exploited by tailoring the novel laminated structure of Ti-TiBw/Ti composites.