Abstract: The effects of Ti microalloying on the microstructure and mechanical property of Mn18 steel were studied， and the reasons for the failure of Mn18 hammer heads were analyzed. The results show that Ti microalloying has the effects of refining grain， increasing impact toughness， elongation， strength and hardness in Mn18 steel. When 0.10% and 0.30% w［Ti］ are added to Mn18 steel， as the Ti content increases， the hardness and strength of high manganese steel increase，and the impact toughness and elongation also show an optimization trend. When it continues to increase Ti to 0. 51%， in addition to the continuous increase of Brinell hardness， the KU2 value and stability， strength stability， the elongation and other indicators all have a downward trend. High manganese steel belongs to high nitrogen austenitic steel， and after adding Ti， a large amount of TiN is rapidly precipitated as a heterogeneous core， playing a series of beneficial roles. If the addition amount is too large， the size of TiN type inclusions is too large and local aggregation occurs， which has a negative impact on the performance stability of Mn18 and is easily prone to fracture and failure of Mn18 steel hammer heads. To ensure its beneficial effect， the content of Ti microalloying used in Mn18 steel should not exceed 0.30%.

Key words: Ti Micro-alloying, Mn18 High Mn Steel, Mechanical Property, Inclusions, Failure of Product

摘要： 研究了Ti微合金化对Mn18钢组织和力学性能的影响，并分析了Mn18钢锤头失效的原因。结果表明，Ti微合金化在Mn18钢中具有细化晶粒、提高冲击韧性、伸长率、强度和硬度等作用，在Mn18钢加入0.10%和0.30%的w［Ti］时，随着Ti含量增加，高锰钢的硬度增大、强度提高，冲击韧性和延伸性也均呈优化趋势，继续增加w［Ti］至0.51%时，除布氏硬度继续增大外，KU₂数值及稳定性、强度稳定性、伸长率等指标均出现下降趋势，高锰钢属于高氮奥氏体钢，加入Ti后迅速析出大量 TiN，作为异质核心，起到系列有益作用，加入量过大，则 TiN类夹杂物的尺寸过大，且出现局部聚集，将对Mn18钢的性能稳定性造成不利影响，也易于导致Mn18锤头断裂失效。在Mn18钢中使用Ti微合金化，为保证其有益效果，其含量不应超过0. 30%。

关键词: Ti微合金化, Mn18高锰钢, 力学性能, 夹杂物, 失效