A novel procedure for measuring the impact fracture toughness K

A procedure is presented for determining the impact fracture toughness K sub Id with precracked Charpy specimens without performing any load measurements. The K sub Id-value is obtained from preestablished impact response curves and a measurement of the time-to-fracture. The measuring technique is fully dynamic and does not impose any restrictions on the test conditions. The applicability of the measuring procedure is demonstrated by determining the impact fracture toughness of two different steels at different test temperatures. (IWM