HIGH-STRAIN-RATE BEHAVIOR OF MICROSTRUCTURALLY-BIASED TWO-PHASE TIB_2+A1_2O_3 CERAMICS

摘要

The high-strain-rate behavior of two-phase TiB_2+A1_2O_3 ceramics with biased microstructures is investigated. Quantitative microscopy was performed to characterize the microstructural bias on the basis of phase size and integral curvature (used as a measure of TiB_2 phase connectivity around A1_2O_3). Dynamic compression and tension (spall) properties were measured, using plate-impact experiments. The measurements used VISAR interferometry and piezoelectric PVDF stress gauges. Finite element simulations of fracture were carried to describe the actual phase morphologies and arbitrary fracture patterns in the microstructures. The results of the quantitative microstructural characterization, high-strain-rate experiments and numerical simulations are discussed.