Abstract：Low carbon Si-Mn steel was processed through intercritical insulation-quenching-partitioning. The plasticity enhancement mechanisms and organizational performance of the Q&P steel were studied by means of field emission scanning electron microscopy, X-ray diffraction and tensile tests. The results show that after intercritical insulation-quenching-partitioning, the steel demonstrates superior comprehensive mechanical property to traditional Q&P steel. Reasonable intercritical insulation time can reduce the secondary quenching martensite content in the organization, so as to ensure better plasticity. The content of retained austenite in the steel is 4.9% after Q&P processing. With the extension of the intercritical insulation time, the content of retained austenite in the steel first increases and then decreases after intercritical insulation-quenching-partitioning. When the steel is intercriticallly insulated at 720℃ for 1500s, and is then quenched and partitioned, the content of retained austenite in the steel reaches the maximum 7.3%, and the comprehensive mechanical property of the steel is the best.
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2014, Vol. 0 
