Work of fracture of PBT/PC blend: Effect of specimen size, geometry, and rate of testing

Fracture behavior of PBT/PC blend was studied at room temperature using two specimen geometries (SENT and DENT) and a wide range of specimen sizes and crosshead speeds. It was found that the fracture of all SENT and DENT specimens is completely ductile and stable. A linear relationship was obtained between the specific total work of fracture, omega(f), and the ligament length, L. Extrapolation of this linear relationship to zero ligament length gave the specific essential work of fracture, omega(e), which for PBT/PC blend was 35 +/- 5 kJ/m(2) and was almost insensitive to geometry and the dimensions of test specimens as well as testing rate.