This study aims at combining modification with dispersion treatment to improve the properties of high manganese steel. The aging microstructures of modified high⁃manganese steel were studied by means of metallographic analysis, SEM, XRD and TEM. Results show that after aging at 460 ℃ for 1 h, the globular separation phases grows in the matrix, spherical precipitates transform into needle over time. When aging at 520℃for 1 h, a small amount of spherical phases precipitate on the grain boundary, fine needle⁃like phases precipitate in the grain. After aging at 580 ℃ for 1 h, the coarse needle⁃like phases precipitate in the matrix, and pearlitic transformation occurs. With the aging temperature increases, spherical precipitates transform into needle, crystal structure of globular phase and needle⁃like one are different, and compared with globular phases, the needle⁃like precipitated phases are more stable. The hardness of modified high manganese steel increases with the increasing of precipitated phases. The key factor on impact toughness and abrasive resistance is fine needle⁃like precipitated phases (Mn,Fe)7C3. The best aging process should make wear⁃resisting precipitated phase precipitate and does not cause the increase of micro strain. The best aging parameter of this experimental steel is aging at 520℃ for 1 h.%为了有效改善高锰钢的组织和性能，通过变质处理和弥散处理相结合的方法，采用X射线衍射（ XRD）、光学显微镜、扫描电镜（ SEM）及透射电镜（ TEM），对稀土－低熔点合金变质高锰钢时效析出相进行研究．结果表明：实验用钢在460℃时效1 h时，基体上开始有球状析出相析出，随着时效时间的延长，析出相由球状向针状转变；520℃时效1 h，晶界上有少量的球状析出相，基体上析出相为细针状；580℃时效1 h，析出相为粗大的针状，且基体发生了奥氏体向珠光体转变．随着时效温度的升高，变质高锰钢时效析出相由球状转变为针状，针状析出相与球状析出相晶体结构不同，针状析出相更加趋于稳定．变质高锰钢的硬度随着析出相增多而升高，（ Mn，Fe）7 C3细针状析出相在冲击韧性和耐磨性起主导因素，变质高锰钢最佳时效工艺应使耐磨析出相析出，且未引起微观应变增大．本次实验用钢最佳时效工艺参数为520℃下时效1 h．
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