DETERMINATION OF THE OPTIMAL QUENCHING TEMPERATURE OF LOW-ALLOY STRUCTURAL STEEL WHEN IMPLEMENTING THE Q AND P PROCESS
DOI:
https://doi.org/10.34185/1991-7848.itmm.2023.01.020Keywords:
phase transformations, martensite, austenite, quenching.Abstract
The work presents practical experience of applying mathematical modeling of the multiphase structural state of low-alloy structural steel 0.30С–0.86Si–1.02Mn–0.84Сr in order to obtain improved indicators of strength and plasticity of the metal. Calculated theoretical optimum quenching completion temperature when implementing the Q&P (Quenching and Partitioning) process for the specified steel. It is shown that the optimal temperature of the completion of the quenching process should be 245 °C, when "fresh" (secondary) martensite is not formed during the final cooling, and the fraction of residual austenite reaches a maximum (approximately 27 % vol.). Austenite stabilization is known to be important in Q&P treated steels to achieve the desired combination of strength and plasticity. The obtained results will be used to develop effective modes of strengthening heat treatment of metal products of responsible purpose with the provision of increased indicators of plasticity and impact strength at ambient temperature.
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