P对铸造S44660超级铁素体不锈钢组织与力学性能的影响

Effect of P on microstructure and mechanical properties of cast S44660 super ferritic stainless steel

摘要:

为了研究P在超级铁素体不锈钢中的作用，基于S44660钢成分，调整了P的质量分数，控制P含量分别为0.004%、0.009%、0.033%以及0.055%四种试验钢，研究了P的含量变化对铸造S44660超级铁素体不锈钢组织与力学性能的影响。结果表明:在P含量为0.004%、0.009%和0.033%时，P含量增加可以扩大S44660超级铁素体不锈钢的结晶温度范围（ΔT），减小晶粒尺寸并提升等轴晶率，但当P含量为0.055%时，晶粒尺寸反而增大，等轴晶率下降；适量的P可以提高材料的室温拉伸性能以及硬度；P对材料冲击韧性具有双重作用，一方面P对晶粒有细化作用，进而提升材料的冲击吸收功，另一方面，过量的P会促使其在晶界处偏聚，进而影响材料的韧性。

Abstract:

In order to study the role of P in super ferritic stainless steel, based on the composition of S44660 steel, the mass fraction of P was adjusted, and the P content was controlled to 0.004%, 0.009%, 0.033% and 0.055%, respectively, and the effect of P content change on the microstructure and mechanical properties of cast S44660 super ferritic stainless steel was studied. The results show that: P can expand the crystallization temperature range (ΔT), reduce the grain size and increase the equiaxed crystal rate when the P content is 0.009% and 0.033%, but when the P content is 0.055%, the grain size increases and the equiaxed crystal rate decreases; The right amount of P can improve the room temperature tensile properties and hardness of the material; P has a dual effect on the impact toughness of the material, on the one hand, P has a refinement effect on the grain, thereby improving the impact absorption work of the material, on the other hand, excess P will promote its deflection at grain boundaries, which in turn affects the toughness of the material.