为了研究含铜超低碳钢等温时效铜析出,对试验钢在950℃固溶,经650℃保温1、20、45h和400～650℃保温1h等温时效后,通过金相、扫描电镜和透射电镜观察及维氏硬度测试揭示等温时效对铜析出的影响规律。试验结果表明随着时效时间的增长,试验钢晶粒尺寸差别不大,但Cu时效析出颗粒的尺寸和形貌存在很大差异,反映在试验钢的平均硬度值发生变化:时效时间为1h时,试验钢硬度值最高,平均硬度值达到189HV;时效时间为20h和45h时硬度值降低,在160HV左右。400～650℃保温1h结果表明随着时效温度增长,试验钢的硬度呈现先上升后下降的趋势。 In order to study the precipitation of isothermal aging copper containing ultra-low carbon steel, the microstructure of the test steel after solution aging at 950 ℃, holding at 650 ℃ for 1,20,45h and holding at 400 ~ 650 ℃ for 1h were studied by metallography, SEM and transmission Electron microscopy and Vickers hardness test revealed the influence of isothermal aging on copper precipitation. The results show that with the aging time increases, the experimental steel grain size difference is not significant, but the size and morphology of precipitated Cu greatly different, reflected in the average hardness of the test steel changes: aging time of 1h , The highest hardness of the test steel, the average hardness of 189HV; aging time of 20h and 45h when the hardness value decreases at about 160HV. The results show that with the increase of aging temperature, the hardness of the test steel first increases and then decreases.