调质工艺对Q690D钢综合力学性能及组织的影响

 以60mm厚Q690D高强度结构钢板为研究对象，在相同轧制条件下，系统地研究了淬火、回火温度对试验钢综合力学性能及显微组织的影响，并对第二相析出进行理论分析。试验结果表明：随淬火温度升高，试验钢强度升高，韧性下降；随回火温度升高，试验钢强度下降，但韧性明显升高。该钢采用930℃淬火(保温10min)650℃回火(保温40min)的调质热处理工艺具有良好的强韧性匹配，综合力学性能最佳，满足国标GB/T 16270—2009要求。

Influences of Quenching and Tempering Process on Mechanical Properties and Microstructures of Q690D Steel Plates

The influence of quenching and tempering process on the mechanical properties and microstructures of the Q690D high strength structural steel plates with 60mm thick based on the same hot rolling conditions, has been studied in detail, including the theoretical analysis of the precipitated second phases. The results show that with the increase of quenching temperature, the strength of the tested steels is increased but the toughness is worse. And with the increase of tempering temperature, the strength is decreased but the toughness is significantly improved. The steel plates show an excellent match of strength and toughness when use the heat treatment process of quenching at 930℃ (preserving the temperature for 10min) and tempering at 650℃ (holding 40min), which meets the requirements of Chinese national standard of GB/T 16270—2009.