In this work, the influence of different heat treatment schemes on structure and mechanical properties of a TRIP steel have been investigated. Following hot rolling, the wire rod was subjected to controlled cooling on a Stelmor line using two different cooling schemes in order to obtain the structure constituents that are typical of TRIP steels (i.e., ferrite, bainite, significant amounts of retained austenite, and perhaps martensite) [1-3]. It has been found that an increase in cooling rate allows for the formation of a bainitic structure, however, retained austenite and/or martensite were not found to be present in the microstructure during optical microscopic examination. The third cooling scheme, performed using a GLEEBLE 3800, allowed for higher cooling rates which enabled the formation of phases characteristic of TRIP steels. It has been proven that for the steel in question (carbon content 0.09 percent, manganese 1.57 percent and silicon 0.90 percent), it possible to obtain a TRIP steel structure which results in a significant improvement in the tensile strength of the wire rod (about 80 MPa) and in the elongation (about 8 percent) compared to properties obtained using conventional and accelerated Stelmor cooling schemes.
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