Abstract High strain-rate (dynamic) shear behavior at different temperatures (25, 150, 300, 450 ℃) of TiB2/2024Al composite prepared by mixed salts method was investigated with a newly designed hat-shaped shear specimen by the improved split Hopkinson tension bar testing, and the shear fracture morphology of the composite was analyzed. The results show that the dynamic nominal shear stress-shear strain curves of the composite at different temperatures were similar. At the initial stage of deformation, the shear strength increased with the increase of shear strain, and when the shear strain was larger than a certain value, the curve showed steady-state rheological features. The shear strength of the composite decreased while the fracture strain increased with the increase of temperature. The fracture of the composite mainly showed features of metal tear ridge and dimples, melted aluminum zones appeared in some local regions, and cracks existed in some TiB2 particles. The size and quantity of voids on facture both increased with the increasing testing temperature.
Received: 15 November 2017
Published: 24 July 2019