High-plasticity TRIP/QP steel above gigabar level and preparation method of high-plasticity TRIP/QP steel

The invention provides a high-plasticity TRIP/Qamp with the plasticity higher than the gigabar level. The invention relates to P steel and a preparation method thereof, and the preparation method comprises the following steps: S1, austenitizing sample steel, rapidly cooling to a bainite phase change zone, and carrying out isothermal phase change for a period of time to obtain steel taking bainite + retained austenite or bainite + carbide as an initial structure; s2, carrying out two-phase region annealing treatment and subsequent corresponding heat treatment on the steel with the bainite and retained austenite structure or the bainite and carbide structure, so as to obtain high-plasticity TRIP steel or Qamp above the gigabar level; according to the high-plasticity TRIP steel or Qamp steel, bainite serves as a starting structure, the full-film-shaped retained austenite is regulated and controlled, the morphology of the retained austenite can be controlled through reasonable component design and effective contr