轧制工艺对800 MPa级高强度调质钢组织性能的影响

EFFECT OF ROLLING PROCESS ON MICROSTRUCTURE AND PROPERTIES OF 800 MPa GRADE HIGH-STRENGTH QUENCHED AND TEMPERED STEEL

以开发800 MPa级高强度调质钢为目的,采用不同的轧制工艺并进行相同的淬火和回火处理,研究了轧制工艺对高强度调质钢组织性能的影响规律。结果表明,试验钢经控制轧制后空冷至室温得到粒状贝氏体及M-A组织,经高温大压下连续轧制后空冷至室温,得到粒状贝氏体和板条贝氏体组织。钢板热处理后均得到高温回火索氏体组织,且两种工艺对钢板的强度影响作用不明显,主要影响其塑韧性。将控制轧制运用到生产实践中,钢板的强塑性得到良好的匹配,各项指标均达到了标准要求。

With the purpose of developing 800 MPa grade high-strength quenched and tempered steel,different rolling processes are used and the same quenching and tempering treatments are used to study the influence of rolling process on the microstructure and properties of high-strength quenched and tempered steel.The results show that the test steel is air-cooled to room temperature after controlled rolling to obtain granular bainite and M-A structure,and after continuous rolling under high temperature and high pressure,air-cooled to room temperature to obtain granular bainite and lath bainite structure.The high-temperature tempered sorbite structure of the steel plate is obtained after heat treatment,and the two processes have little effect on the strength of the steel plate,mainly affecting its plastic toughness.Applying controlled rolling to production practice,the strong plasticity of the steel plate is well matched,and all indicators have reached the standard requirements.