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This paper presents an overview on the super strengthening phenomenon that takes place during intensive quenching (IQ) of steels. It is shown that for obtaining an additional strengthening of material, one should pay special attention to whether the part cooling rate within the martensite range is high enough and whether compressive stresses are formed at the surface of steel parts. For hardening high carbon alloy steels with a low martensite start temperature, a two-step quenching procedure is recommended. At the first step of quenching, the martensite transformation is delayed, and, at the second step of quenching, the part cooling rate is accelerated within the martensite range. For hardening low and medium carbon steels, an IQ-3 quench method is recommended when a so-called direct convection cooling is applied for providing a maximal cooling rate within the martensite range and maximal compressive stresses at the surface of steel parts. To calculate a part cooling rate within the martensite range, a generalized equation is provided. Data on mechanical properties for different steels proving a presence of the super strengthening effect are provided also. A practical use of the super strengthening phenomenon is discussed in the paper.