不同稀土、硫含量重轨钢的组织与性能

Structures and Properties of Rail Steel with Different RE and S Contents

研究了具有不同稀土、硫含量重轨钢的组织与性能·在低硫重轨钢中 ,稀土元素具有使硫化物夹杂改性、抑制先共析铁素体析出以及细化NbC析出相等作用·稀土的加入明显改善钢的纵向力学性能 ,当加入量为 0 .0 2 %、钢中稀土硫比w(RE) /w(S) =1 5 7时 ,钢的强度、韧性及抗疲劳性能最佳·在高硫重轨钢中 ,稀土的加入可使硫化物明显改性 ,但对钢的纵向力学性能影响不明显·当稀土加入量相同时 ,高硫重轨钢的力学性能明显低于低硫重轨钢 ,这表明硫含量是影响重轨钢性能的重要因素·

The structures and mechanical properties of rail steels with different RE and S contents were studied. In low S test steel, rare earth has the attractive effects. The shape and properties of the sulfides may changes. The addition of rare earth reduces the quantity of pro eutectoid ferrite. When rare earth added is 0 02% or w (RE)/ w (S)=1 57,the low S test steel has high strength, toughness and fatigue limit. In high S test steel, rare earth can also change the shape and properties of the sulfides, however it has little effect on longitudinal properties. The mechanical properties of the low S test steel are better than that of the high S test steel,when the RE contents are same in both steels.