新型Si-Mn系贝氏体钢的连续冷却转变组织及性能

The Microstructure and Mechanical Property of a New Type of Low Carbon Si-Mn Bainitic Steel Under Continuous Cooling

通过热模拟试验对Si—Mn系低碳贝氏体钢的连续冷却组织进行研究。结果表明，该系列贝氏体钢在冷却速度大于1℃／s的条件下，可得到全贝氏体组织，冷却速度对组织类型和性能有直接影响，抗拉强度可达到1000MPa。通过合适的轧制工艺控制，可得到细小的贝氏体组织，使产品具有良好的塑性和冲击性能。

The microstructures of low carbon Si-Mn bainitic steel under continuous cooling were studied by thermal simulation test. It is shown that the whole bainitic microstructure could be obtained when the cooling rate is more than 1.0 ℃/s. The cooling rate has a direct effect on the type of microstructures and properties. The ultimate tensile strength of the whole bainitic microstructure could reach 1 000 MPa. Fine bainitic structure could be obtained with good plasticity and impact properties through the proper controlling of rolling process.