Instrumented Impact Testing of Low-Carbon Steels

The mechanical properties of a low-carbon steel and a Swedish iron have been examined over a range of temperatures from − 196 to 150°C by means of an instrumented impact test. Load vs. temperature curves exhibit similar features to curves obtained from notch bend tests. The effects of specimen geometry and microstructure on the fracture stress have been studied and the results are discussed in terms of a critical tensile stress for slip-initiated cleavage fracture.