目前，基于非均质高温奥氏体来调控先进高强钢的组织和性能，引起研究学者的广泛关注。为进一步明晰合金元素非均质程度对组织和性能的影响，指导先进高强钢的设计，本工作采用以Mn配分的珠光体为初始组织的快速淬火-配分工艺，研究了奥氏体化时间和温度对高温奥氏体中非均质Mn分布的影响规律，进一步探讨了微观组织和力学性能的演变。结果表明，高温奥氏体的Mn分布能够调控淬火过程的马氏体转变。当高温奥氏体继承了珠光体中富Mn渗碳体和贫Mn铁素体中的Mn分布时，淬火后可获得富Mn片状残余奥氏体与贫Mn马氏体板条构成的鬼珠光体组织。随奥氏体化保温时间的延长和温度的升高，高温奥氏体中Mn元素非均质程度减弱，导致鬼珠光体组织减少，块状残余奥氏体和粗大板条马氏体数量增多、且尺寸增大。随着保温时间的延长，屈服强度由于细晶强化的减弱而降低；均匀延伸率由于块状残余奥氏体的增多而升高，颈缩后的延伸率因块状残余奥氏体形成的脆性马氏体而降低。由于残余奥氏体和马氏体的含量随着奥氏体化工艺不发生改变，使得抗拉强度和断裂总延伸率也不发生变化。由此可见，通过改变奥氏体化的工艺参数，能够在保证高抗拉强度(约1700 MPa)和高断裂总延伸率(约20%)的基础上，实现对屈服强度和均匀延伸率的进一步调控。

The ever increasing demand for safe and lightweight steel has promoted the development of advanced high-strength steel (AHSS). Recently, many AHSSs have been developed through chemical heterogeneity, resulting in microstructure refinement and mechanical property optimization. Although many efforts emphasize the construction of Mn-heterogeneous high-temperature austenite (γ-Fe), the influence of Mn-heterogeneous distribution remains unclear. In this work, different austenitization times and temperatures are applied to Mn-partitioned pearlite, followed by the same quenching and partitioning process. The effect of Mn distribution in high-temperature austenite on the microstructural evolution and mechanical properties is systematically investigated. Results show that the Mn-heterogeneous high-temperature austenite can tailor the austenite-to-martensite transformation during quenching. The Mn-depleted austenite is then readily transformed into lath martensite, and the Mn-enriched austenite is mainly retained as film roughness (RA), both of which assemble the ghost pearlite. With an increase in austenitization time and temperature, the Mn atom diffusion from the Mn-enriched austenite (originated from cementite lamellae) to the Mn-depleted one (originated from ferrite lamellae) increases, leading to the decreased chemical heterogeneity in high-temperature austenite. Thus, the fraction of ghost pearlite decreases while the fraction and size of blocky RA and coarse lath martensite increase. A wider lath martensite lowers the strength of the yield or the elastic limit of steel. The increased fraction and size of blocky RA ensure an increased uniform elongation by transformation-induced plasticity effect, whereas the transformation product (i.e., fresh martensite) is detrimental to the post-uniform elongation. Meanwhile, because the fractions of RA and martensite hardly change with austenitization condition, the ultimate tensile strength (about 1700 MPa) and total elongation (about 20%) are relatively constant. Therefore, tuning the Mn distribution in high-temperature austenite provides an effective strategy to tailor yield strength and uniform elongation while maintaining large ultimate tensile strength and total elongation.