Hardening of St. 3 steel by shock-wave action

A method for studying the strength characteristics of multiphase media based on construction of microhardness histograms is developed. It is shown that for St. 3 steel, the microhardness histograms are divided into two groups based on the type of high explosive used: histograms with one maximum and those with two maxima. Using the method proposed, we determined the contribution of zones consisting mainly of ferrite and pearlite grains and zones of multiple distortions to hardening of St. 3 steel. The behavior of these zones under annealing, various pulse actions, and long-term storage is studied. It is shown that under shock-wave action, zones with predominant pearlite and ferrite grains are hardened synchronously.