Today, advanced steels which are used in the automotive industry are required to possess high strength and ductility. Two heat treatment methods capable of meeting these requirements were tried in the present experimental programme that involved selected types of steels. These methods were the Q-P process (Quenching and Partitioning) and intercritical bainitic annealing. Favourable elongation levels combined with high ultimate strengths were obtained by stabilizing the retained austenite in the microstructure. The Q-P process, which can produce mixtures of martensite and a certain amount of retained austenite, led to strengths above 2000 MPa and elongation levels of 10-15 %. The intercritical annealing, which results in combinations of bainite, ferrite and retained austenite, provided strengths of up to 2000 MPa and elongation levels up to 25 %.Keywords: Q-P process, intercritical annealing, retained austenite, AHSS
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